Athletic are one of the most unique clubs in the world. With their Basque-only policy and a passionate support, this is a club for the working-class, and they are proud of their heritage. Despite criticism that the policy has held them back, the locals are proud of the fact that their players are exclusively from the Basque region: it gives them a deeper sense of attachment to the club, one that keeps them coming in their droves to San Mamés.

While the same Basque-only mantra doesn’t apply to the coaching staff, there are some individuals who’ve enhanced that sense attachment, bringing the fans closer to the squad. One such person was Marcelo Bielsa, a vivid thinker who became one of the greatest innovators of this generation.

His work at Newell’s Old Boys was impressive, with his football easy on the eye, and the league title, as well as a Copa Libertadores run in 1992, added to his gleaming reputation. Such was his impact at the club that the Argentine side later named their stadium after him, and when he arrived in Bilbao, there was an appreciation of how he’d stuck to his philosophy in good times and bad; much like the club has remained Basque-only.

His introductory press conference to the people of Bilbao was conducted via Skype, where, amidst the obligatory questions of why he chose Athletic and his plans for the upcoming season, he explained that he had spent hours researching the team and conducting a study of the previous season. He went into great detail, showing off just what many had expected of him, and in a humorous tone, he ended the meeting by thanking the press for the tolerance they had shown during the event.

He stressed that he wanted to honour the commitment he had made to his employers – that of bringing attacking football positive results to the north of Spain. Having already watched all 38 of Athletic’s LaLiga games from the previous season, writing about them on colour-coded spreadsheets and plotting a route to improvement, this was a man who wanted to win at all costs.

The club’s president, Josu Urrutia, a former player who had just won the recent elections, promising the arrival of Bielsa as part of his campaign, was under as much pressure as the manager. He needed to deliver and, staying true to the club’s policy, he brought in Ander Herrera, a midfielder who was born in Bilbao but began his career with Real Zaragoza.

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Herrera would prove to be a key cog in Bielsa’s midfield. The high-octane energy he brought to the side fared well in the midfield alongside the attack-minded Óscar de Marcos and the defensively astute Ander Iturraspe. The triumvirate were perhaps the most important figureheads in the team, and they were supported elsewhere by confident young players such as Javi Martínez and Iker Muniain.

The man from Rosario was pleased with what he had to work with, and in that same video he spoke highly of the team’s “fighting spirit and willingness to work”, adding that he was happy with the combination of seniority and youth. The core of that squad – the players mentioned above, along with the names such as Mikel San José and Markel Susaeta – were all under 25, while others like Fernandos Llorente and Amorebieta were both under 30. In addition, these players had vast experience despite their tender years, with several of them having played over 150 club matches and having represented the national team.

The hype around him was palpable – the people were already buying into the Bielsa hysteria and were keen to adopt him as one of their own. Hundreds came to watch his first training session and were left impressed with what they saw. These were encouraging signs.

However, his competitive start was poor, resulting the club’s worst start to a league campaign in 32 years. His first five matches would see Los Leones gain just two points from home draws against Rayo Vallecano and Villarreal – two struggling sides – the latter of which would succumb to relegation at the end of the campaign. The enthusiasm shown by the fans in pre-season would simmer down, but fortunately for Bielsa, there was a chance to rebuild his reputation during the Basque derby against Real Sociedad.

With the calmness and intensity that Bielsa promised when he arrived at the club, Athletic earned a crucial away win, a brace by Llorente sealing an important 2-1 success. This would be the catalyst for change at San Mamés.

Between the win over Real Sociedad at the start of October and the halfway point of the season in mid-January, Athletic would lose just once, at home to Granada. The team were intense, covering so much ground and playing with pressure on the opponent, characteristics typical to any Bielsa team. It isn’t easy adapting to a new method, especially if the person teaching the new strategy is someone as meticulous as Bielsa, but the players had shown their desire to improve.

Athletic, prior to the Argentine’s arrival, had rarely settled into a definitive style, flitting between physical, direct football and some moments of attacking flair over the decades. Now, however, their football was, along with Pep Guardiola’s Barcelona and José Mourinho’s title-winning Real Madrid, the best in the league, easy on the eye with forward movement, using the flair of Muniain and Susaeta on the flanks and adjusting the pace in the final third to build attacks but also hit the opposition on the counter.

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Perhaps the most impressive of Bielsa’s results came in the Europa League, where they won their group having overcome the likes of Red Bull Salzburg, Paris Saint-Germain and Slovan Bratislava. In the round of 32, they were to make another trip east when they were drawn against Russian outfit Lokomotiv Moscow, who they beat by virtue of the away goals rule.

As was often the case with Bielsa’s high-octane methods, his teams would often suffer from burnout towards the end of the campaign. That season, along with their league and continental commitments, they were also progressing well in the Copa del Rey. To avoid suffering the problems which had so often dented his teams’ hopes in the latter stages of the season, Bielsa would pay attention to the depth and versatility at his disposal. Gaizka Toquero and San José were frequent substitutes, while Martínez’s ability to play in midfield and defence came in handy.

The problem of burnout, though, couldn’t fully be prevented. Athletic suffered a poor finish to the league campaign, but that wasn’t before the biggest highlight of their season and, arguably, one of Bielsa’s most important wins in his career. After their victory against Lokomotiv in the previous round, Los Leones were drawn against Manchester United in the Europa League last-16.

In the first leg at Old Trafford, they suffered an early scare after Wayne Rooney scored, but Llorente got them level just before half-time. In the second half, they turned up the energy once again. Fast-paced, Sir Alex Ferguson’s United were unable to cope and were outdone by the brilliant Bielsa. De Marcos and Munain scored two more goals, and although Rooney netted a penalty in stoppage time, the favourites were now on the edge of elimination.

After the match, an awe-inspired Old Trafford rose in unison to salute this fantastic young team – they knew what it was like to see football this good, and all they could do in defeat was appreciate the quality of the victorious opposition.

A week later in Bilbao, Llorente and De Marcos scored again to put the tie out of reach as Athletic went through. No controversy, no drama; just good football that would impress the neutral. Schalke awaited the Basque outfit next.

Before that, however, there would face several tests. The size of the squad was a challenge for Bielsa, and despite rotating before and during matches far more than he was accustomed to, a lack of players eventually caught up with Athletic. They suffered a slump in LaLiga, despite doing well in Europe and the Copa del Rey, where their good football was met with a fortunate draw. En route to the final they faced Oviedo, Albacete, Mallorca and Mirandés, having little trouble in their bid to reach the climax against Barcelona.

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From March until the end of the season, Athletic suffered seven defeats in their final 13 games and won just three – a run of form that resulted in a 10th-place finish in the league. All their attention was now on the Europa League. Against Schalke, they showed the form that made them such a revered outfit across Europe, a 4-2 win in Gelsenkirchen in the first leg making the return fixture a formality. The second leg finished 2-2, but Bielsa’s team had little trouble in making the semis, where Sporting CP would provide them with a stern test.

They lost the first leg 2-1 in Lisbon, despite taking the lead, and Sporting, another young team, looked likely to hold out in the second. But Bielsa’s plans worked out again as Sporting struggled to handle Athletic’s pressing and energy, losing 3-1, which meant that Los Leones would face Atlético Madrid in the final.

In the Europa League final in Bucharest, they arrived as slight favourites. The Madridistas had endured an inconsistent season that saw a managerial change as Diego Simeone took the reins. However, all predictions were thrown out by half time as Radamel Falcao scored twice. The fatigue in the side was evident as a crestfallen Athletic played the second-half without the same zest that many were accustomed to. Diego scored late on to seal a 3-0 win. It was heartbreak once again for Bielsa.

Sixteen days later, they travelled to the Vicente Calderón to face Barcelona in Guardiola’s final match at the helm of the Catalans. A month prior to this, it was rumoured that Bielsa may be managing the Blaugrana next season – indeed, Guardiola was a known admirer. But all that was put aside during the final, where Barcelona would run riot. A Lionel Messi goal was sandwiched by a Pedro brace as Barça struck three times within the first 25 minutes to condemn Athletic to another final defeat.

The season was, on paper, a failure, but there had been clear progress and stunning wins along the way. It was Athletic’s best campaign since the 1980s, and yet there was nothing to show for it. Bielsa, a man who had never won a major trophy in Europe and last won any competition nearly 15 years earlier, saw his methods questioned. Was he a choker when it mattered most? Is his intense training to blame for two visibly tired and exhausted displays from a young, emerging Athletic?

It was a strange season, one that promised so much and saw them play some of the most entertaining football in Europe. There was much to cheer about but nothing to celebrate.

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During the summer, the players were reportedly met with Bielsa’s famed fury. There were reports that some of the members of the squad were overheard laughing after the defeats and Bielsa wanted to bring the players back to Earth, suggesting they were disrespecting the fans. All it meant was that the road to the end was now firmly being walked on. The sale of Martínez to Bayern Munich was a huge loss, while Bielsa replaced the ever-present Llorente with Aritz Aduriz.

Another talking point in this souring relationship was the dispute between Bielsa and a builder working on the club’s training facility. Traditionally a calm and humble figure, Bielsa was enraged by the fact that the construction work on their Lezema facility was well behind schedule, saying that its condition was an insult to him and the players. Amazingly, he simmered back down to his cool self, deciding to file a police complaint …against himself. “I’m sorry,” he said, “he may well be the worst site manager around, but he deserved respect.”

The next season was a major disappointment. Their participation in the Europa League and Copa del Rey were over almost as soon as they started. In Europe, they finished third in a group consisting of Lyon, Sparta Prague and Isreali side Ironi Kiryat Shmona, while in the Copa, they were knocked out by Eibar courtesy of the away goals rule after the two-legged affair finished 1-1 on aggregate. There was nothing to contend for, and their league form was tepid.

They finished 12th LaLiga, maintaining the one step forward, two steps back scenario that they’d fallen into at the end of the previous season. For the fans, there were many heavy defeats that season, including 5-1 hammerings at Real Madrid and Barcelona, 4-0 defeats to Espanyol and Atlético, and a double loss against Real Sociedad. In the end, they conceded 65 league goals – the fourth most in the league and more than that of Real Zaragoza, who finished last. Unsurprisingly, at the end of the season, with the squad divided, the board decided against extending Bielsa’s contract.

In hindsight, these were two illuminating years, with action aplenty on and off the pitch. There was exciting football in the first season, but that couldn’t carry on during the next. Yet, there was this sense of achievement that he had played a huge role in the development of several players and took an underachieving club to heights they hadn’t experienced in over two decades. Popular with the people of the city, he had changed the working philosophy at Athletic.

There’s a story from his first season in charge, where a group of kids stopped Bielsa on the street with the aim of getting their sticker book signed. He had a better idea, taking the sticker book with him and asking the children to return to the same spot the next day. A man of his word, he returned 24 hours later with a sticker book of signatures from the entire squad. The trophies may not have arrived as many thought they could, perhaps should, have, but Bielsa was popular, humble and committed – as he often has been.

By Karan Tejwani @karan_tejwani26