The biggest obstacle to Pep Guardiola winning another Champions League, it is widely accepted, is Pep Guardiola. There cannot be a Manchester City knockout tie in the Champions League without talk of his tendency to overthink. The most dramatic moment of last season’s final came when the lineups were released an hour before kick-off and neither Rodri nor Fernandinho were included. It’s what elevates Guardiola above the throng: he is not merely a great manager, but also a flawed hero: he is Faustus, he is Oedipus, he is Charles Foster Kane. It didn’t used to be like that. He used to win Champions Leagues. When his Barcelona beat Manchester United in the 2009 and 2011 finals, there was no trickery beyond switching Samuel Eto’o and Lionel Messi a few minutes into the game in Rome. His side went out with swagger and outplayed United as they had been outplaying opponents all season. It’s only more recently – the four midfielders away to Liverpool in the 2018 quarter-final, adopting a back three against Lyon in the 2020 quarter-final, the absence of a holding midfielder against Chelsea in last season’s final – that the mysterious tweaks have become a habit. This perhaps is the flip side of experience. He knows what can go wrong, but in trying to avert that ends up disrupting the structures and systems that make his side great, the strengths that are why they should win. That is why it matters City face Atlético Madrid on Tuesday in the first leg of this season’s quarter‑final. Because of all the defeats Guardiola has suffered in the Champions League, none haunts him as much as Bayern’s semi-final elimination against Atlético in 2016, none made him more determined to, as far as possible, take chance out of the game. Guardiola had left out Thomas Müller for the first leg, in Spain, a decision that provoked consternation and, perhaps, increased the pressure. Bayern went 1-0 down early to a superb Saúl Ñíguez goal but were probably the better side until, with 20 minutes remaining, Guardiola removed Thiago Alcântara for Müller. Bayern lost momentum and ceded the midfield and, with Fernando Torres hitting the post, they were slightly fortunate to get away with a 1-0 defeat. This was it. Bayern were closing in on their third straight Bundesliga title under Guardiola, but they always won the Bundesliga – doing it with greater verve or tactical control meant little. They had lost in the Champions League semi-final in the two previous seasons: unpicked on the break by Carlo Ancelotti’s Real Madrid in 2014 and blown away in the first leg by Luis Enrique’s Barcelona in 2015. Guardiola’s legacy rested on this: lose and there would be an inevitable sense of anticlimax. He knew this was a direct examination of him and his ideals – because so few other managers construct a side so thoroughly in their own image, and because Diego Simeone’s vision of football is so directly contrary to that. Guardiola identified a vulnerability between Filipe Luís, Atlético’s left-back, and Stefan Savic, the left-sided centre-back. That channel was usually protected by Koke but Guardiola believed Philipp Lahm could be used to draw him away, creating opportunities for Müller. He also suspected that Atlético, although they would settle back into their familiar low block, would press hard from the start to try to pinch an early away goal, so resolved to go long to Robert Lewandowski, switching to a more familiar possession-based game when Atlético dropped off. He was right. His plan nearly worked. It should have worked. A Xabi Alonso free-kick gave Bayern the lead before half-time and Müller missed a penalty soon after. But nine minutes into the second half, Atlético caught them on the break, Torres playing in Antoine Griezmann to equalise. Lewandowski levelled the aggregate scores with 16 minutes left and Torres missed a penalty but Atlético went through on away goals. Bayern had 73% possession in the second leg, 33 shots to Atlético’s seven. They had the better of all but about 25 minutes of the 180 and scored as many goals as Atlético. And they were out. It had happened to Guardiola before. His Barcelona had lost implausibly to Internazionale and Chelsea in semi‑finals in 2010 and 2012. But here was another level of disappointment and frustration. How could it keep happening? At that point, Guardiola had suffered five Champions League eliminations. Bayern’s defeat to Barcelona in 2015 was readily explicable: Barça were the better side, Guardiola gambled on surprising and unsettling them by pressing high and operating a back three in the Camp Nou and it didn’t work. But in the other four, his team had been undone on the break, three times after being almost laughably dominant. Guardiola teams press high. They leave space behind them. It is a vulnerability in the method: to call it a flaw is misleading because it is what makes them great – and in football no blanket is ever big enough. It may be that better sides are less intimidated by the high press, are better able to exploit that vulnerability. It’s understandable that Guardiola should seek to mitigate the danger. For a coach as interventionist as Guardiola, it must be very difficult just to write off defeats as being down to misfortune. Imagine the alternative: imagine the mockery if he just kept sending out his sides with the same approach and they kept being caught on the counter. But it is hard to believe that if those semi-finals of 2010, 2012 and 2016 were played multiple times, Guardiola would not win most, that his recent attempts to counter the counter, those odd selections against Liverpool, Lyon and Chelsea, have not become counter-productive. Now Atlético again, so that for the first time since 2016 Guardiola will come face to face with the team that has provoked such doubt. This is not a great Atlético. From a purely footballing point of view, City should win relatively easily. But this is not purely about football. For Guardiola, it’s an enormous psychological test.