Football never stops changing. Possession is constantly being killed and then resuscitated. And teams are always chasing the latest trend: Countless clubs across Europe have tried to emulate the passing and positional play of Pep Guardiola’s Barcelona or the full-throttle pressing of Jürgen Klopp’s Borussia Dortmund. Nothing ever stays the same — apart from, perhaps, the long balls and ultra-deep defending of a Tony Pulis team.

To be a long-term success, a manager has to keep adjusting to such an unstable, progressive environment — and if he doesn’t, he’ll fall behind.

When José Mourinho first arrived at Chelsea in 2004, he dubbed himself “a special one.” And his team’s performances backed up what seemed to be absurd egomania. Coming on the back of an incredible Champions League win with FC Porto of Portugal, Mourinho’s team proceeded to dominate the Premier League, winning six titles in his three years, with an outstanding defence, reinforced by the additional midfielder of a 4–3–3.

During his first stint with Chelsea, Stamford Bridge was an impenetrable fortress, fortified by Mourinho and his charges, who didn’t lose a single league game at home. After leaving the club in 2007 — first moving to Inter Milan, where he won the Champions League, and then leaving Milan for Real Madrid, where he won a single league title — Mourinho returned to Chelsea in 2013. He now dubbed himself “The Happy One,” and the fortress seemed rebuilt. After a transitional first season, his second brought the desired Premier League title, and José was on top of England once again. Yet, less than a year later, Mourinho had lost nine of 16 league games and was out of a job.

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Now the manager of Manchester United, the 53-year-old’s most recent outing in West London also ended in disaster. This time Mourinho was in the away dugout, watching on as his star-studded Manchester side was decimated by his former club, 4–0. On the opposite side, Chelsea manager Antonio Conte has improved the club by 14 points, compared to where they were under Mourinho at this point last season. But it isn’t just Conte who has replaced Mourinho.

The Special One’s initial arrival in England signaled the beginning of the end for a number of managers who couldn’t adapt to his revolutionary defense and counterattacking game. Now, with United in sixth place and already six points away from the Champions League places, Conte, Klopp, Guardiola, and Mauricio Pochettino might be returning the favor.

Mourinho’s sides are famous for their concrete defenses, but his United team has shown some cracks. They’re allowing 3.6 shots on target per game, which is a fraction better than league average and nowhere near the standard set by Mourinho’s past.

A big feature of his first months in Manchester has been the team’s shift from a man-marking defensive scheme under previous manager Louis van Gaal to more of a zonal focus. It was a priority of preseason training, with Mourinho looking to make his imprint on a defense that was already good under Van Gaal. While holding midfielders Marouane Fellaini and Ander Herrera would’ve previously followed their man tightly when out of possession, they’re now required to stick to their positions and maintain a more stable shape, less reactive to opposition movement.

In theory, this can have a number of benefits: (1) they’re not as susceptible to off-the-ball movement, (2) they aren’t as isolated individually and can offer more cover to teammates, (3) it better suits Mourinho’s deep and reserved defensive style.

So far, it hasn’t worked. When opponents have possession of the ball, United are often too passive in applying pressure from their defensive block. While sitting deeper on defense is a completely viable strategy, a degree of pressure is still required to stop the opposition from making a key pass. Without the challenge of an immediate defender, it’s so much easier for the on-ball attacker to split open the defense.

Compare this to the style of Mourinho’s new competition. Klopp is defined by his team’s defensive pressure, and under his guidance Liverpool have quickly become the best-pressing team in the league. Close behind are Pochettino’s Tottenham Hotspur, who play with a similar up-tempo style based more on a man-to-man approach than the Merseyside club. Mourinho’s biggest rival, Guardiola, is another exponent of a pressing game, as he prefers his teams to win the ball back as soon as it’s lost.

In their higher pressing, these teams immediately have an advantage over their opponents. They significantly increase the possibility of regaining possession deep in the opposition third, and the early closing-down can help to disrupt an attack before it really begins. Their pressing increases the tempo of the match, and it gets attacking players, like Liverpool’s hyperactive Senegalese winger Sadio Mané or Tottenham’s über-creator Christian Eriksen, on the ball while the defense is unsettled. This would seem to benefit the team-tactical-genius of Henrikh Mkhitaryan or complete threat of Paul Pogba, but Mourinho prefers not to risk leaving his team exposed, as can happen when a press gets broken.

Except, the passivity of United’s defense becomes even more problematic when coming up against these faster-playing rival teams. Since their better opponents tend to have more possession, Mourinho’s side defend deeper, with the wingers joining the defensive line to create a 6–3–1 shape. In these moments, the lack of wide support for the central midfielders gives them even more space to cover. Plus it means even more time for dangerous attackers like Eden Hazard, Kevin De Bruyne, or Philippe Coutinho to make something happen.

Granted, when Mourinho’s teams were winning titles, there was still space and time on the ball to be had for opposing attackers. But Mourinho’s teams were so organized that opponents would struggle to break through no matter how much time they had on the ball. But United’s defense is far from what he had with Inter Milan or during his first tenure with Chelsea.

And herein lies the bigger issue: If Mourinho’s team isn’t playing at an elite defensive level, there’s not much else it does well.

No one’s ever fallen in love with a Mourinho team because of all the goals it’s scored. Every single one of his teams was almost an antithesis of the Barcelona project he was rejected from in 2008, when the flowing passing of Guardiola was chosen ahead of Mourinho’s defense-first approach. Despite adding about £125 million of talent in Paul Pogba, Zlatan Ibrahimovic, and Henrikh Mkhitaryan to his team’s attack this summer, his defensive-minded football won’t change.

Under Van Gaal, the team was frustratingly patient, rarely pushing the ball vertically and often seemingly possessing the ball for nothing other than possession’s sake. While that’s no longer the case, the attack still doesn’t move fast enough to unsettle opposing defenses. Outside of Manchester City, Liverpool, Chelsea, Tottenham, and Arsenal, most teams will sit deep against United and force center backs Chris Smalling and Eric Bailly to pass the ball out from the back. With the technically limited Fellaini as the deepest midfielder (whose only actually good performances came as a striker for David Moyes at Everton), Pogba, and even Ibrahimovic — their star striker — is often required to drop deep, and help progress the ball forward.

In either case, Mourinho’s side are immediately faced with a dilemma.

If Ibrahimovic drops deep, then the pressure on the opponent’s defensive line becomes almost nonexistent. Although United have extra numbers to bring the ball forward, they then have fewer options to advance the ball to. Furthermore, it’s a misuse of Ibrahimovic’s abilities — he’s a perfect target for direct passes and a phenomenal finisher in the penalty area, but he can’t drop and create from deep like a Lionel Messi or a Francesco Totti.

The other option is Pogba. For £89.3 million, United have gotten themselves a player who combines complete athleticism with elite technique. He can dribble his way through three defenders as easily as he can shield them off with his strong frame. Aside from this, his threat from distance is well-documented across Vine and YouTube.

But he can’t do what he does best when he’s receiving the ball from his center backs 60 yards from goal. A long shot is out of the question, and a dribble in such an area should only be attempted by Barcelona’s ice-cold pivot, Sergio Busquets. United are asking Pogba to progress the ball from deep, but if you’re going to break the transfer record for Pogba, you don’t do it because of his passing.

Without a deep player to effectively move the ball through the middle, United’s attacks are often confined to the wider areas of the pitch. (Mourinho played the pass-first Michael Carrick in a deep role in Saturday’s 3–1 win over Swansea, but suddenly relying on a 35-year-old to facilitate your attack raises more questions than it answers.) While Spanish attacking midfielder Juan Mata can improve this slightly by offering an option in these tight spaces, he can’t fix their issues by himself.

The majority of their attacks, therefore, come through the likes of wingers Marcus Rashford, Anthony Martial, and Jesse Lingard, with the fullbacks in close support, but that’s about it. And while all three are fine players, they’re not who United paid more than £100M for. The dangerous and expensive central players stay central, and they make little-to-no attempt to offer support to their wide teammates. You can often see their structure grouped into two sections; the wide attack of two to three players, and the rest of the attack waiting in the middle.

From here, there’s basically one option: cross the ball into the box and hope Ibrahimovic gets onto the end of it. You can’t bring the ball back inside when there’s no one there to pass to, and so the attacks become isolated.

Compared to United, the likes of Liverpool and Manchester City are much more centrally focused. Klopp’s attacking approach is to play extremely vertically through the team’s inside attacking midfielders. And at United’s in-city rivals, the central pairing of attacking midfielders in David Silva and Kevin De Bruyne has been the shining light in Guardiola’s start.

The main reason for playing down the center is that from there you have access to the whole field. Both wings are just a pass away. If the ball is positioned on one touchline, the opposite half of the pitch becomes useless. And in Manchester United’s case, the lack of players to link the wing to the center simply makes things even worse.

Considering the problems creating a dynamic and unpredictable attack, the continued omission of Mkhitaryan from United’s 11 makes little sense. The Armenian has played just 107 minutes this year, and it’s not because of injury issues; Mourinho just won’t use him. But Mkhitaryan’s most valuable quality is also exactly what United need: supportive movement off of the ball that connects the team’s overall structure. It made him Borussia Dortmund’s key player last year, and while there’s clearly something going on behind the scenes, his services should be vital to the team’s stuttering attack.

With that being said, United’s attack isn’t completely harmless, as they can create through individual moments. The three most prominent examples being the pace of Rashford, Ibrahimovic’s ability to convert difficult opportunities, and Pogba’s shooting threat from distance

Yet their inability to create connections between these star attackers is the reason they’re still playing like a Europa League side, and why Pogba’s early performances don’t even put him in the top 10 players in the league.

These issues aren’t new to Mourinho, and they highlight his lack of development as a coach. His teams have typically been poorly connected in possession, with a much greater focus on the individual talents and attacking in transitional moments.

Such a playing style is fine when you have a well-drilled defense and a potent attack (see: Diego Simeone’s Atletico Madrid). But United have conceded more goals than newly promoted Middlesbrough, and their attack is what you would expect of a Mourinho team. By playing in such a reserved manner, they’re inviting pressure onto a permeable defense and minimizing the attacking opportunities for the attackers they paid so much money for.

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In contrast to Mourinho’s static philosophy, Guardiola’s teams may all play with the same pass-first style, but the tactical differences between Barcelona and Bayern were significant. While the Catalan club were fixated on playing through the central diamond of Busquets, Xavi, Iniesta, and Messi, the focus in Bavaria was much wider through the direct dribbling of Franck Ribéry, Arjen Robben, Kingsley Coman, and Douglas Costa. At Manchester City, his varying use of the fullbacks as orthodox, in-between, or full-on central midfielders is an example of his perpetual evolution.

And then there’s the man who Mourinho is essentially replacing: Sir Alex Ferguson managed United for 26 years and remained flexible all the way up until his last season with the club.

Mourinho’s limiting and overly cautious approach has been enough to win the tactical battles of the past, yet with the new batch of young and progressive managers in the league, can the same be said for the future? He hasn’t had a full season out of management since joining Inter Milan eight years ago and in this time, his tactical ideas have failed to develop and correct themselves. What’s more: While Mourinho’s previous teams seemed to reach their highest heights in part because of the emotional connection between the manager and his players, his tenure at United has been characterized by his postgame sniping at the inadequacies of his squad. Even in Saturday’s 3–1 over Swansea, one of the team’s better performances this season, he criticized the desire of some of his defenders: “There is a difference between the brave, who want to be there at any cost, and the ones for whom a little pain can make a difference.”

Whatever the pain threshold of their back four, Manchester United will ultimately be just fine. They’re performing around the level of the sixth-best team in the league, and all of the teams ahead of them are very good. The squad is talented and filled with potential, especially Martial, Rashford, and Pogba. But that’s the issue: You don’t spend upward of £100 million and hire José Mourinho to be just fine.