Perhaps Bayer Leverkusen always believed. But this was the moment when the rest of us could too. For Bayern Munich this was a kind of televised humbling: a blow not just to their title hopes but to their sense of identity. Through the peaks and troughs of this season we have been told that Thomas Tuchel’s team would eventually show their true selves when it really mattered. And they did; just not remotely in the way anyone expected.

In the end Bayern were simply outclassed: Tuchel bested by Xabi Alonso, Bayern beaten not just in practice but in theory. Bayern’s trophy-laden players – for the most part, anyway – had no answer to Leverkusen’s quirky angles and relentless off-the-ball running, their defensive solidity and ability to move as one unit. And Tuchel simply had no answer to Alonso’s tactical flourishes, his surprising selections, his use of the bench.

From the very first minutes it felt as if Bayern were chasing the game, second-guessing themselves, second-guessing each other. Álex Grimaldo scored the game-clinching goal but was mainly a roaming agent of chaos on the left. Florian Wirtz, nominally an attacking playmaker, was doing pretty much whatever he wanted.

The result was a game with all the textural quality of a David Lynch movie: thick with intrigue and red herrings, strange motifs and hidden layers of meaning. Why were fans throwing sweets onto the pitch? Why was Stanisic the only player on his team not celebrating his goal? Why were Bayern’s full-backs playing on opposite sides? Where was Leverkusen’s striker? And why was there a home fan dressed as the Pope?

Some of these questions were easier to answer than others. The sweets, which delayed kick-off by eight minutes, were part of a long-running protest by fans across Germany at a proposed deal selling off a stake in the Bundesliga’s media rights to private investment. The fancy dress was for Karneval weekend. Stanisic is currently on loan from Bayern. And perhaps Tuchel’s decision to play Sacha Boey at left-back was an attempt to counter the pace of Jeremie Frimpong, who ended up not starting.

Really, this was just one of the ways in which Alonso seemed to have Tuchel’s number from the start. The decision to leave out a recognised striker in Patrik Schick in favour of a false nine in Amine Adli was another: one of the reasons Bayern’s defence looked so uncertain was that it was never entirely clear what they were trying to defend. Bayern saw much more of the ball, but after some modest preamble it was Leverkusen who took control of the game.

And this has been one of the underrated qualities of Alonso’s Leverkusen all season: the ability to switch between gears in the same game, different tactics in the service of the same strategy. It took 18 minutes for them to unlock Bayern for the first time, Adli set free by a brilliant pass from Wirtz but tackled by Kim Min-jae. Bayern were still sleeping when the next phase of play began, Robert Andrich crossing for Stanisic to slam in at the far post.

Meanwhile, Harry Kane solemnly toiled away in the Harry Kane role – a kind of Super Bowl tribute in which he tried to be quarterback, tight end and cheerleader all at once. For all this, against the league’s best defence, Bayern really didn’t have the faintest idea how to get him into the game. They were still sleeping when Nathan Tella had a volley saved at close quarters, still sleeping when Adli was sent clear by a gorgeous Granit Xhaka pass.

And five minutes into the second half they were sleeping when Grimaldo bounced the ball off Tella and continued, untracked, into the area to drill it in at the near post.

That was the cue for Tuchel to go back to Plan A: returning to a back four, restoring his full-backs to their regular sides, bringing on Joshua Kimmich and Thomas Müller. And yet it was the home side who ended the game stronger: in injury time Frimpong, finally on as a substitute, added a sensational third with Manuel Neuer still up for a corner and nowhere to be seen. As a metaphor for the title race, it felt as powerful as any.

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