At the beginning of May 2015, Chelsea wrapped up the Premier League title with a scrappy 1-0 win over Crystal Palace. It was not a great game or a great performance – for a couple of months Chelsea had looked exhausted, dragging their fatigued limbs over the line and grateful no contender was able to mount a serious challenge to them. It was a day of relief as well as exultation, manager José Mourinho’s third title with the club, his first since he returned in 2013 for his second stint as manager, and only the fifth Chelsea had ever won, despite all the recent investment from their billionaire owner Roman Abramovich.

Nobody then, perhaps, realised quite what a struggle those final yards had been, or had any notion just how difficult things had become. Certainly nobody suspected then what would happen this season as Chelsea suffered the worst opening third to a campaign of any defending champion. Nobody recognised that what we were seeing was not necessarily a wearying champion staggering to the finish but a club entering a period of profound crisis.

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Mourinho’s mood, too, was strange. He could have been forgiven for seeming jaded, yet his performance in the post-match press conference was neither tired nor celebratory. Usually such end-of-season events are relaxed affairs: “Tell us how you won”, “Who was the most important player?”, “Which game was key?”

But Mourinho was as chippy as ever. This day of joy, he decided, was the perfect time to deliver another thrust in his ongoing feud with Pep Guardiola, the intense 44-year-old who was appointed Barcelona manager ahead of Mourinho in 2008. Guardiola, a much-loved former Barça player, had no coaching experience beyond one year in charge of the reserve side, but went on to win three league titles and two Champions Leagues in four seasons at Barça, playing a style of football widely regarded as both thrilling and revolutionary. “For me,” Mourinho said, “I’m not the smartest guy to choose countries and clubs. I could choose another club in another country where to be champion is easier.” He didn’t name Guardiola, but the reference was clear. In 2013, Guardiola had gone to Germany’s super-club, Bayern Munich, where the question is less, “Who will win the title?” than “How many will Bayern win it by?” Guardiola’s titles, Mourinho was suggesting, meant less than the one he had just won. To some extent he was right, of course, and if he had been making a general critique of the iniquities of global football finance, he might even have come across as statesmanlike, but his point was limited to Guardiola and his personal antipathy.

“I took a risk,” he went on. “I am so, so happy because I won another Premier League title 10 years after [my first] in my second spell at the club. I was champion at every club I coached. I came to Inter [Milan], Real Madrid and Chelsea. Every title is important. To win the title in Spain with 100 points against the best Barcelona ever was a big achievement that I enjoyed so much. Maybe in the future I have to be smarter and choose another club in another country where everybody is champion. Maybe I will go to a country where a kitman can be coach and win the title. Maybe I need to be smarter but I still enjoy these difficulties. I think I’m at the right place. I’m here until Abramovich tells me to go.”

Even by Mourinho’s standards, this was weird. Why would anybody, having just lifted the title, choose to belittle their rival, a rival who operates in another country? And not just a passing jibe, a full-on assault.

In hindsight, that final sentence seems strange too: here until Abramovich tells him to go? Mourinho had said on his return to Chelsea that he wanted to found a dynasty, that in a career laden with silverware that was something he still had not done and yet that line, seemingly so throwaway, hinted at an insecurity. Perhaps it was merely part of his contract negotiations: he did, after all, sign a new four-year deal a few weeks later.

Odd as the attack on Guardiola was, it followed a pattern. Increasingly, as the season had gone on, it had become apparent that Mourinho was obsessed by Barcelona and, specifically, by Guardiola as the manifestation of the Barcelona philosophy that, since his successes at the club, had become hugely influential among the elite. He was once among them, but they rejected him. He had once worked with Louis van Gaal at Barcelona in the 1990s, at a time when the club was home to the men who would shape modern coaching.

Mourinho left to make his fortune and succeeded, but when he wanted to return they denied him. He was a little bit different. He was not a player but a translator-turned-coach. He was not one of them. He did not think like them. He looked at the game and asked not how to win while playing well, but simply how to win. He had a pragmatic edge that meant he never quite fitted in. He came, in 2008, replete with honours, wanting to be coach and they preferred one of their own. He became the outcast, the rebel, the fallen angel. He began to define himself in opposition to Barcelona and thus to the prevailing footballing ethos of the age. He would not play by their rules; he would do things his way in self-conscious opposition and prove that he was right. He vowed, like Milton’s Satan “to wage by force of guile eternal war, irreconcilable to our grand Foe”.

Facebook Twitter Pinterest José Mourinho (right) shakes hands with Pep Guardiola before the Champions League semi-final first leg match between Real Madrid and Barcelona, in 2011. Photograph: Sergio Perez/Reuters

When Louis van Gaal arrived at Barcelona in 1997, having managed Holland’s biggest team Ajax for the previous six years, it was supposed to be as the club’s youth coordinator. But he was soon asked to take over as manager as Bobby Robson was shuffled into an ambassadorial role because of poor league form. Mourinho had started out as Robson’s interpreter with the Portuguese club Porto, but had impressed the former England manager with his understanding of football and had followed him to Spain as a translator-cum-coach. On Robson’s recommendation, Van Gaal took on Mourinho to be his “third assistant”. At 34, it was a huge step for Mourinho, the first real sign that he was respected by figures at the top of the global game.

Mourinho had been born into football. His grandfather had been president of Vitória, a moderately sized club from Setúbal. His father had been a goalkeeper and then went into coaching. Mourinho wanted to be a player but at the age of 24, after spells at three of Portugal’s smaller clubs, he too accepted that coaching offered him a brighter future. His father’s career helped make Mourinho aware what an ungrateful world football can be: Mourinho has often referred to the time, when he was “nine or 10”, that his father was sacked on Christmas Day. Actually, it happened in 1984 when Mourinho was 21, but the general point remains: no matter what you’ve done in the past – Mourinho Sr had taken Rio Ave to promotion and a Portuguese cup final – a run of bad results can bring the end.

Mourinho Jr became a student at the Instituto Superior de Educação Física in Lisbon, Portugal’s leading sports university, and came under the influence of Professor Manuel Sérgio, who believed that football knowledge was not enough, that a coach also had to be a psychologist, a public speaker and have a grasp of the sciences. In 1987, Mourinho left the college and worked for a while as a PE teacher at various primary schools, specialising in helping children with disabilities.

As a teenager, Mourinho had helped his father, preparing scouting reports on opponents – perhaps significantly, looking for ways their style of playing could be hampered. When he was 28, Vitoria de Setúbal, the club where his father had played and coached, took him on as a youth team coach. He fulfilled the same role at Estrela de Amadora and then became a scout at Ovarense, two of Portugal’s less glamorous clubs. Eventually, in 1992, he got his big break, appointed to work with Robson, who was then manager of Sporting Lisbon.

Robson, a naturally open and generous man, took to discussing tactics with Mourinho and, as they moved to Porto and then Barcelona, gave him more and more responsibility, getting him to plan training sessions and prepare dossiers on opponents, recognising that the younger man’s meticulousness and natural caution were a useful counter-balance to his own spontaneity and attacking instincts.

Barcelona in the mid-90s was an extraordinary place to be, not just because the team won the league two seasons running, but because of the people who were there. In Mourinho’s time at the club, it was home not only to the future Chelsea manager, but also the current managers of Bayern Munich, Barcelona, Manchester United, Porto, PSV Eindhoven and Southampton. They are not clones of each other, but it was at Barcelona in the late 90s that the prevailing ethos of modern football was formed.

The predominant style was that which has sustained Barcelona since the arrival of the Ajax coach Rinus Michels in 1971. He brought with him Total Football, a belief in possession football, rooted in a high offside line, pressing and the interchange of players on the field and, in 1973, the great Dutch forward Johan Cruyff. When Cruyff became Barcelona’s manager in 1988, he reinforced this philosophy and, although he saw the version of the game practised by his successor as manager, Louis van Gaal, as overly mechanised, the starting point was the same. This was perhaps the greatest coaching seminar in history, and the philosophy it taught was that which had been flowing from Ajax to Barcelona, which believed the same things but had more money, for three decades: what we might perhaps term the Barçajax school.

Facebook Twitter Pinterest Mourinho with Bobby Robson at Sporting Lisbon in 1992. Photograph: Action Images

Not that anybody remarked upon it then, but Mourinho was an outsider looking in. He had not played at Ajax or Barcelona, so although much of his experience at the top end of football had been under Barçajax thinkers, those ideals perhaps were not as deeply ingrained in him as they were in others. Van Gaal was impressed by his work on positional play and allowed him to give tactical advice at half-time and to coach the team in friendlies. As he became increasingly confident, Van Gaal found “an arrogant young man, who didn’t respect authority that much, but I did like that of him. He was not submissive, used to contradict me when he thought I was in the wrong. Finally I wanted to hear what he had to say and ended up listening to him more than the rest of my assistants.”

Barcelona was Mourinho’s education. The next stage was to put it into practice. After a short spell in Lisbon at Benfica, Mourinho was appointed coach of União de Leiria in July 2001. They are a small club and their budget was extremely limited, but playing hard-nosed counter-attacking football Mourinho had them third by January. They fell away towards the end of the season but Portugal’s big clubs had taken note and, the following January, Mourinho was appointed manager of Porto.

It was at Porto that Mourinho’s ideas were first tested on a stage he saw as befitting his talents. It was there that he first achieved the sort of control over a side that he demanded, it was there that he began competing for titles rather than scrapping to avoid relegation.

At Porto, Mourinho would vary his team’s formation according to whether he was playing in the domestic league or the European Champions League. The shape, though, was a minor detail alongside the style. “He wanted us to press very high,” said Maniche, a midfielder in Mourinho’s team. “He wanted the team to react quickly when they lose the ball, so we gain it in their midfield. This pressure would be done as a team, and not only one or two players.” But, crucially – in contrast to the Barçajax school of thought – possession was never fetishised. “The more the ball circulates in midfield,” Mourinho said, “the more likely it is that the other team will dispossess us.” That was the first expression of a theory that would later become notorious.

Mourinho would always present his team with dossiers on their opponents. “One of the most important aspects about José, which I support, is that the other team has to be the one making the changes, you have to keep your own identity,” said Costinha, who was Porto’s defensive midfielder at the time. “Of course, he would give us detailed information about the team we were facing next at the start of the training week and more precisely about the player that would be closest to our area of play. ‘What was the player like? Did he have a tendency to get many cards? What kind of movements did he make?’ It was new for many of us back then, but it was very helpful and meant we were much better prepared for each match.”

Where Mourinho excelled was in his attention to detail and, specifically, in anticipating scenarios that might occur during the game. “Sometimes it was as though he could see the future,” said goalkeeper Vítor Baía. “I remember a specific incident against Benfica, when throughout the week he prepared us for what we should do after we scored a goal … He told us that [the Benfica coach José Antonio] Camacho would make a specific substitution and change his tactics, which was what happened. So we already knew what to do when he did it; we were completely prepared for it. For the same match, we also prepared to play with 10 players, because José knew the referee would not be able to take the pressure and would show a red card along the way. That also happened … so we knew what to do and got a narrow win.”

Mourinho still readies his side for different scenarios today. When Chelsea beat Paris Saint Germain 2-0 in the quarter final of the Champions League in 2014, for instance, John Terry revealed that they had practiced for various different scorelines, even down to the heavily attacking system they ended up using for the final 10 minutes as they chased the vital second goal. Specific preparation is key; as little as possible is left to chance.

Mourinho’s other way of preparing for big games was psychological. “The rivalries would do their work,” Maniche said, “and the press conferences.” An ability to play the media has always been a Mourinho strength, antagonising opponents and pressuring referees. The flipside of that is his relationship with his own squad, a capacity to create remarkably strong bonds.

That, perhaps, is an aspect of Mourinho that is often overlooked, that while he can be grouchy with the media, while he pursues feuds with rivals and can fall out with his own players, he is also capable of inspiring devotion. There are stories of players in tears as he hugged them goodbye on his first departure from Chelsea. “He would fool around with us outside practice, but when the time to work arrived he would be ruthless,” said Baía. “We only practiced for one hour each day, yet those hours were the most intense I’ve ever seen.”

While he pursues feuds with rivals and can fall out with his own players, he is also capable of inspiring devotion

Baía stresses how good Mourinho was at handling different personalities, what an astute man-manager he was. “He knew everybody so deeply that he could control our emotions in every situation,” he said. “In my case, he would just pat me on the back and I was ready to go. However, there were players who needed motivation, who needed to be praised, and he knew which ones needed what, that’s what made him so good.”

That, though, is not quite the full story, which explains much about Mourinho’s Machiavellian charm. In September 2002, Baía was banned from all club activities for a month after a training-ground row with Mourinho. The goalkeeper said that he had a “great relationship” with Mourinho, having worked together for many years when Mourinho was an assistant coach. “But when he arrived at Porto he wanted to show everyone who was the boss: friends off the pitch, players on it. Performance was what counted, not relationships.”

Porto won the league with a record points tally and also claimed both the Portuguese Cup and the Uefa Cup, their approach in the final infuriating the Celtic manager Martin O’Neill, who accused them of diving, feigning injury and timewasting. They defended the league title the following season and also added the Champions League, a remarkable achievement in the modern era for a team of Porto’s stature. In 2004, Mourinho made another step up and was appointed manager of Chelsea.

Given the rush of success that followed, given how Mourinho charmed English football in his first season, it is easy to forget now that his first weeks at Chelsea were faltering – at least from a tactical point of view. In his first six matches, Chelsea conceded only one goal and picked up 14 points, but they only scored six goals. Mourinho spoke about the importance of practising the transitions from attack to defence and defence to attack, and introduced to public consciousness the concept of “resting on the ball”, passing it around at the back to give players time to recuperate, but his football was scratchy and, frankly, a little dull.

Against Middlesbrough in September 2004, though, he changed shape to the 4-3-3 that became characteristic of that period at Chelsea, and everything began to click. Lampard fell back into a shuttling midfield role in which he excelled, specialising in those late runs into the box that brought him 13 goals that season. Mourinho was more cautious than he had been at Porto. The shift away from the Barçajax model had begun. Remorselessly, relentlessly, Chelsea swept to the title.

The only problem was the suspicion that Roman Abramovich felt that having invested as much as he had, he might be due a little more entertainment. The next season, Chelsea conceded seven goals more and won four points fewer, but they still won the league by some distance. But the whispers about Abramovich’s dissatisfaction were growing ever stronger. He wanted more exciting football. So he bought more stars.

Mourinho was unimpressed. And the attempts to integrate some of the big signings, most notably Andriy Shevchenko, had little success. During the 2006-7 season, Chelsea were still defensively solid, but they lacked anything approaching fluency. The relationship between Mourinho and Abramovich soured as the season went on, reaching crisis point in a League Cup semi-final first leg at Wycombe. After his injury-hit team struggled to a 1-1 draw against the League Two side, Mourinho erupted. In a small room off the tunnel at Wycombe’s ground, as a tea urn belched steam into the freezing January air, he bemoaned, in his characteristically sulky way, a recruitment policy that had left him overburdened with attacking players but bereft of defensive cover.

Mourinho lingered a further eight months after the rant in the steam, but the atmosphere became increasingly rancorous and, by the end of September 2007, he was gone.

The following summer, Barcelona fired their manager and began the search for his replacement. Txiki Begiristain, Barça’s technical director, interviewed Mourinho, telling him that the final decision would be taken by Johan Cruyff, who held no official position but who, as the living embodiment of the Barçajax ethos, had an authority that transcended the club’s politics. Mourinho, determined to press his case, called the club president Joan Laporta and asked to speak to Cruyff. Laporta replied that the decision had already been taken: Barça were going to appoint the inexperienced Pep Guardiola. Mourinho told Laporta he had made a terrible mistake.

Facebook Twitter Pinterest Frank Rijkaard, during his time as coach of Barcelona in 2004, speaks to Johan Cruyff, the embodiment of the Barça approach to playing football and a highly influential figure at the club. Photograph: Lluis Gene/AFP/Getty Images

In his book Goal: The Ball Doesn’t Go in by Chance, the then Barcelona CEO Ferran Soriano stated that the decision came down to a straight head-to-head between Mourinho and Guardiola. “It was clear that Mourinho was a great coach but we thought Guardiola would be even better,” said Soriano. “Mourinho is a winner, but in order to win he guarantees a level of tension that becomes a problem.”

Mourinho has never forgiven Barcelona.

That same summer, not long after his rejection by Barcelona, Mourinho became manager of Inter Milan. As at Chelsea, he favoured heavily defensive tactics. Inter won the league in his first two seasons, and in the 2009-10 season, they also won the Champions League for the first time in 45 years.

The final, a 2-0 win over Van Gaal’s Bayern Munich, was straightforward enough, but the symbolism of Mourinho overcoming his former boss was overshadowed by the far greater resonance of the semi-final in April 2010, and Inter’s extraordinary backs-to-the-wall triumph over Guardiola’s Barcelona, the defending champions. In the first leg, which was in Milan, Mourinho had the great good fortune that the eruption of the volcano Eyjafjallajökull meant that Barça had to travel to Milan by bus, which perhaps partly explained their sluggish performance in losing 3-1.

But it was on his opponent’s home turf, the Camp Nou, that Mourinho had his revenge on Barcelona and Guardiola. Inter Milan had a player sent off after 29 minutes, at which point Mourinho’s team went even more defensive, dropping all nine remaining outfielders behind the ball and at times seeming as if they were deliberately giving away possession so as not to lose their defensive shape. Again and again Barça swept forward and again and again they encountered an impenetrable mass of black-and-blue shirts that denied them the space for their rat-a-tat flurries of passing.

Inter had only one shot on goal in the entire match – Barcelona had 15 – and just 19% possession, but they lost just 1-0, and therefore won an aggregate victory; in so doing, they struck a blow against Barça and all they stood for. When Barça turned on the sprinklers as the Inter players celebrated, Mourinho must have been even more delighted: he hadn’t just won, he had provoked Barça into an act of pettiness and so helped dislodge their halo.

Inter only ever seemed like a stepping-stone. The sense was always that Mourinho was eyeing a return to either England or Spain. They were where the money and the real power was – which of course made the fact he has won Champions Leagues with clubs from outside the very elite all the more impressive. And, perhaps most importantly, Spain was where Barcelona and Guardiola were.

Barça had dominated Spanish football under Guardiola, infuriating Florentino Pérez, the president of Real Madrid, Barça’s great rivals. After Inter’s victory over Barcelona, it began to seem that Mourinho was the man who could topple Guardiola’s Barcelona side. Such was the desperation to bring his empire down that Pérez’s quibbles over Mourinho’s style of play were pushed to one side. The club appointed him in summer 2010.

When Madrid went to the Camp Nou on November 29, they were a point clear at the top. This was the moment Madrid had been waiting for, the moment when Mourinho was supposed to show he could bring down Guardiola. His plan was to do what he had done seven months earlier, to pack players behind the ball and look to frustrate Barça. But Barcelona’s personnel had changed in the intervening time, and they now presented a different, more mobile threat. Within 14 minutes, Barça were 2-0 up. Mourinho had Madrid push higher, but it didn’t work. Barça won 5-0.

Madrid only lost another three games that season, but that wasn’t good enough. Barça won not only the league title but also the Champions League, beating Madrid in the semi-final. In Diego Torres’s controversial and highly critical biography of Mourinho, he states that Real Madrid’s increasingly negative tactics annoyed certain players. (The book relies on excellent – if partisan – sources within the dressing room.)

Torres suggests that Mourinho at Madrid was not motivated merely by winning – which had been almost his sole objective elsewhere – but by the desire to do so in his way, to establish himself as a tactical pioneer. Mourinho spoke repeatedly of the trivote, his triangle of aggressive, hard-tackling midfielders who could either win the ball back high up the pitch or offer an impenetrable block in front of the defensive four. Mourinho was so attached to this system that he played it at times when, as Torres’s sources saw it, it was of limited benefit and meant using players out of position. It was as though Mourinho was determined above all else to promote his own legend.

The Champions League semi-final was played out in a sulphurous atmosphere, largely of Mourinho’s making. Madrid did little but spoil: even if Barça did dive and whinge, at its heart the rivalry had become about one team passing and dribbling, the other kicking and brawling; light against dark, football against anti-football. In Mourinho’s 17 matches against Barcelona as Madrid manager, his side committed 346 fouls to Barcelona’s 220.

According to Torres, Mourinho laid out a simple seven-point plan for winning big games:

1) The game is won by the team who commits fewer errors.

2) Football favours whoever provokes more errors in the opposition.

3) Away from home, instead of trying to be superior to the opposition, it’s better to encourage their mistakes.

4) Whoever has the ball is more likely to make a mistake.

5) Whoever renounces possession reduces the possibility of making a mistake.

6) Whoever has the ball has fear.

7) Whoever does not have it is thereby stronger.

This is the antithesis of the Barçajax approach, a categorical rejection of the possession-based, proactive approach of Guardiola and his ilk. It was precisely how Inter had played in that Champions League semi-final but there was always a sense at Madrid that it was somehow unworthy of the club.

The bitterness between Guardiola’s Barça and Mourinho’s Madrid carried over into the following season, and was exemplified by a Barça-Madrid match that ended with two red cards in injury time and a brawl in which Mourinho poked Tito Vilanova, the Barça assistant coach, in the eye from behind. It was an act of cowardice and petulance that would have profound consequences.

On 7 May 2013, towards the end of a disappointing season for Madrid, Mourinho arrived alone at the Sheraton Madrid Mirasierra to prepare for a league game against Malaga, having refused to travel with his players after accusing them of disloyalty. A contingent of the Ultras Sur, who saw themselves as Madrid’s most devoted fans, were waiting for Mourinho with a banner that proclaimed their love for him. There was effectively a state of open warfare between Mourinho and the club captain Iker Casillas. That Mourinho’s fractious time at the club was coming to an end was not in any real doubt. And for Mourinho, things were about to get much worse.

That night, the story broke that Manchester United were going to appoint David Moyes as a successor to Alex Ferguson. According to Diego Torres in his biography of Mourinho, the Madrid manager was appalled. He had believed that he had a special relationship with Ferguson, but the outgoing United manager had not even called him to let him know of the decision. That night Mourinho was restless, fretful, constantly checking the news to see if there may have been some mistake. The following morning he called his agent Jorge Mendes to see if it might be possible to derail the deal and reinsert himself into the picture.

By the following day, Mourinho was insisting that his intention had always been to go back to Chelsea, that his wife wanted to live in London. Perhaps that was true, but perhaps he saw this as a second betrayal. Worse was the sense that this was a decision that was only indirectly related to football. “A United manager,” Bobby Charlton, at the time a United director, told the Guardian in December 2012, “would not do what he did to Tito Vilanova … Mourinho is a really good coach, but that’s as far as I’d go.” And his behaviour at Madrid had raised other doubts. “The problem is,” one executive at Gestifute, Mendes’s agency, told Torres, “when things do not go well for Mou, he does not follow the club’s line. He follows José’s line.”

By then, his options were limited: other than Paris Saint Germain, Chelsea was the only club of sufficient stature who would still have him. Not only that, but he was, at least, going back to a club where he had been revered, where he had announced himself as “a special one” and been loved for it, where the fans did not seem to mind – perhaps even relished – his pragmatic approach.

In summer 2013, Mourinho arrived at Chelsea promising that he had mellowed, that he was now “the happy one”. With creative players such as Oscar and Eden Hazard operating behind a striker, there was even an attempt to play more spectacular football. That lasted until December, when Chelsea lost to Sunderland in the League Cup quarter-final. After the game, Mourinho, looking tired and dishevelled, spoke of going back to basics. He had nine days before Chelsea played again and when they did, they stifled Arsenal in an utterly tedious 0-0 draw. Afterwards, Mourinho seemed positively jolly. Chelsea conceded just four goals and went unbeaten through the following 13 league games, although a series of surprise defeats derailed their title challenge and they finished third.

The next season, Chelsea won the league comfortably. As their progress to the title became more and more certain – even though they showed signs of fatigue – the focus shifted away from who would win and towards how a champion should play. Chelsea, better than any other side in England, could close down a game when they needed to and so the question began to be asked whether they were boring. “That question doesn’t even make sense to me,” said Jorge Costa, who is now manager of Gabon. “It’s obvious the most important aspect of coaching is winning. I hated to lose when I was a player, and I still hate it as a coach. I really don’t think there was a team playing better than Chelsea last season.”

For former Porto player Maniche, the question is naïve. “Those critics have no idea of what football is, apparently. Arsenal seem to enjoy having a coach who does not win titles, but ask their fans if they wouldn’t like Mourinho better. What would you prefer? You need to win, and to win, you need Mourinho.”

Mourinho himself is unapologetic about prioritising winning. “There is no kid, even playing with his cousin or his father, even in the garden, there is no kid that plays to lose,” he said in May. “The nature, the sense of it – doesn’t change. They play to win. And football at the highest level, that’s even more so.”

That is not how Van Gaal sees it. “He has more belief in defence than attack,” the Manchester United coach told Patrick Barclay for his biography of Mourinho. “My philosophy is always – because I believe we must entertain the public – to have attacking play. His philosophy is to win! That is the difference.” (There is an element there, surely, of Van Gaal playing to the gallery. A number of the teams he has managed – including United – have not been notably attacking.)

“There is no new generation,” Mourinho went on, criticising the Barçajax purists who seem to regard possession-football as the only true way to play (although not Guardiola, a distinction Mourinho tends to ignore). “If you don’t play counter-attack then it’s because you are stupid. Because counter-attack is a fantastic item of football. It’s an ammunition that you have and when you find your opponent unbalanced.

“Coaching is about recognising the good qualities of the opponents and recognising the fragilities of the opponent,” said Mourinho in April 2015, after a comfortable but unlovely 1-0 win over Manchester United. “And, more than that, it’s to recognise the good qualities of my team – and the bad qualities of my team. Because my team also has bad qualities, and it’s very important that me and my players, we recognise our bad qualities. One of the secrets of good coaching is, ‘Can you hide your bad qualities from your opponents and even from the pundits?’”

Hiding the bad qualities became harder this season. This was only the third time that Mourinho had reached a third season with any club he had been at. On the previous two occasions – at Chelsea the first time round and at Real Madrid – things had gone horribly wrong.

It was Béla Guttmann, the great Hungarian coach, who noted that “the third season is fatal”. His theory was that after two seasons a coach had said everything he had to say, that the style of play would become predictable, that players would no longer be motivated by the familiar calls to arms, that complacency and decline would inevitably set in. That’s the entropic imperative against which all coaches must constantly fight; only a very few – such as Sir Alex Ferguson – succeed.

There is perhaps a particular issue with Mourinho in that so much of his method relies on his abrasiveness. He conjures conspiracies to forge a siege mentality, he picks fights that often exist nowhere but in his imagination, and gradually this wears people down. Journalists and the public roll their eyes as he makes yet another passive-aggressive claim that referees are against him, directors tire of his constant hustling and players perhaps weary of his intensity.

That, at least, is the theory. Even before the season began, on Chelsea’s July tour of the US, Mourinho had perhaps sensed then that there was something amiss, had felt the lack of hunger, had recognised that certain players had begun to doubt him. As the team stumbled through the start to the season, Mourinho went through his familiar repertoire. He initiated a handshake spat with Arsenal’s manager Arsène Wenger. He publicly berated two members of his medical staff for treating a player who it turned out was only feigning injury. Eva Carneiro, the team doctor, subsequently left the club and mounted legal proceedings against both Chelsea and Mourinho. Within a few weeks, Mourinho’s decision began to reveal itself as a terrible miscalculation – not just because of any wrong done to Carneiro personally, but because of her position in the dressing-room.

Facebook Twitter Pinterest Eva Carneiro, the then Chelsea team doctor, argues with Mourinho after she treated a player on the pitch on the opening day of the season, in August. Photograph: BPI/REX Shutterstock

Medical staff, bound as they are by the confidentiality of their profession, often become significant figures in a team’s dynamic. They spend time talking to players while treating or examining them, and players realise that they can trust them. A player may be troubled by, say, a potential problem in his calf that he does not want to tell the manager about for fear of being dropped – but he will tell the doctor, who has a duty to investigate and offer advice. A discussion of personal life is often part of the diagnostic process. Issues broached will sometimes be psychological, perhaps especially in sport, in which self-confidence is such a major factor. The doctor becomes a trusted outlet. Carneiro, it seems, was popular among the players: ostracising her was politically a dreadful move.

After a series of disastrous performances and results, matters reached a head on 3 October, when Chelsea lost 3-1 to Southampton. Under pressure, Mourinho counter-attacked. On Sky he spoke uninterrupted for seven minutes: “I want to make it clear … 1) I don’t run away; 2) If the club wants to sack me, they have to sack me because I am not running away from my responsibility, my team … 3) Even more important than the second, I think this is a crucial moment in the history of this club. You know why? If the club sacks me, they sack the best manager this club had. And secondly, the message is again the message of bad results. The manager is guilty. This is the message, not just these players, the other ones before, they got [the message] during a decade. This is a moment for everybody to assume their responsibilities. To stick together. This is what I want.”

Nobody was quite sure how to take it. The monologue was spectacular, and also included a ludicrous attack on the referee Bobby Madley and the refereeing establishment in general, as well as a call for everybody at the club to “take responsibility”. On the one hand it appeared he was flailing wildly, lashing out at enemies real and imagined. But the point about Chelsea’s reputation was a sound one. That Mourinho had been reappointed was itself an indication of how few elite-level managers there are still available to Chelsea. Nobody who dreams of building a dynasty would go there. And yet equally there was the thought, stimulated by the Torres book, of whose line Mourinho was pursuing: was what he said good for him or good for Chelsea?

As results faltered further, others began to wade in. “Mourinho is a great coach but, after a year and a half, he ruins his players,” said the former England manager Fabio Capello.

Mourinho is a great coach but, after a year and a half, he ruins his players Fabio Capello

Chelsea beat Aston Villa, but then came a defeat at West Ham in which a Chelsea player was sent off just before half-time. Mourinho approached the referee Jon Moss in the tunnel and called him “fucking weak”, which led to him being banned from attending the next Chelsea match. Was that a genuine loss of control or was this another example of the trait outlined by Torres of him helping create the appearance of conspiracy to absolve himself of responsibility?

Last Thursday, the present cycle came to an end as Mourinho returned from a staff Christmas lunch to find Eugene Tenenbaum, a Chelsea director and one of Abramovich’s closest allies, waiting in his office. Ten minutes later, Mourinho had left the club “by mutual consent”. The final straw was a defeat the previous Monday by the surprise league-leaders Leicester City, managed by, of all people, Claudio Ranieri, the genial Italian ousted to make way for Mourinho when he first arrived at Chelsea in 2004. After that game Mourinho had railed in three separate interviews against those who had “betrayed” him. He explained he was referring specifically to a failure to follow defensive instructions but the term seemed to have far greater resonance. He believed a player had leaked his team line-up to Porto before their meeting in the Champions League at the beginning of December, while his relationship with certain key players had manifestly decayed: Diego Costa tossed his training bib at Mourinho after not being introduced as a substitute at Tottenham, while Eden Hazard batted away an attempted hug as he left the pitch in that Porto game. The day after Mourinho’s departure, Chelsea’s sporting director spoke of “palpable discord”.

Facebook Twitter Pinterest Mourinho worked with Van Gaal at Barcelona. Is there a chance he may succeed him at Manchester? Photograph: Nigel French/PA

What happens now? Mourinho has spoken of wanting an instant return to management and his insistence that he is settled in London seemed an unsubtle hint that he wants another job in the Premier League. With Van Gaal under pressure at Manchester United, it may be that he ends up succeeding his former mentor. On Sunday, Guardiola announced his departure from Bayern at the end of the season, with Manchester City his likely destination. This sets up the possibility of a rematch between Mourinho and his greatest rival – at two clubs that are already fierce local rivals. Yet there must be caution. In the eight seasons after taking the Porto job, Mourinho won six league titles and two Champions Leagues. Since going to Madrid in 2010 he has won just two league titles. Very few managers thrive at the very top for more than a decade: it is an emotionally and psychologically gruelling profession and football is always changing; the process of perpetual evolution is draining. It may be that Mourinho’s best is past.

A week after the win over United last season, Chelsea drew 0-0 at Arsenal, to which the home fans chanted: “Boring, boring Chelsea”. Mourinho responded sarcastically. “People talk about style and flair but what is that? Sometimes I ask myself about the future, and maybe the future of football is a beautiful green grass carpet without goals, where the team with more ball possession wins the game. The way people analyse style and flair is to take the goals off the pitch.”

It’s a fine, memorable image – but then the devil always has the best lines. Part of Mourinho’s appeal is his cynical charm. Even Milton seemed to relish Satan’s role rather more than those of the denizens of heaven: he was, as William Blake observed, “of the devil’s party without knowing it”.

The irony of Mourinho’s position is that if, as it often seems, he has allowed his philosophy to be defined in opposition to Barcelona – he is that which they are not – then he is still allowing Barcelona to dictate terms. As the obsession with Guardiola suggests, Mourinho may have rejected Barcelona as they rejected him, but as the anti-Barcelona he is still defined by them. It may be that the negativity that induces places limitations on how long he can prosper.

This is an edited and updated version of a piece from the latest issue of The Blizzard.

Illustration by Ellie Foreman-Peck

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