Hello darkness my old friend. As Pep Guardiola walked on to the pitch at the final whistle in the Bernabéu, a familiarly skinny-legged figure, that gleaming bald pate looking terribly tender under the hard white lights, still dressed head to toe in tailored black like a celebrity magician, or a university lecturer on his way to a funeral, it was hard not to feel the pathos of the moment. Guardiola shook hands, patted his players and said something to the referee. He lingered near the centre circle, facing down the waves of triumphalism from the seats, in an arena where this really is personal, where Guardiola stands as a gargoyle of deep tribal rivalries. Often managers use that post-match lull as a buffer before their media duties, a moment to compose their thoughts and prepare a face to meet the faces. This was a crushing night for Guardiola, one of those moments around which a career is defined, horizons reeled in. But City have another game on Sunday, at Newcastle, with another prize on the line. Guardiola knew this was a moment to swallow it down. A little later he would tell his press conference that he had at no point seen defeat coming, or had any idea Real Madrid were capable of turning a game like this. Really? Because it was out there in plain sight. In the press seats one Spanish football correspondent had flagged up that defeat was coming to Manchester City even as they dominated possession early on, growing ever more certain of Madrid’s eventual victory as Riyad Mahrez put City 1-0 up on the night. And while this may be a familiar pattern for those who have studied this Madrid team at close range, the question remains: how did City manage to lose this game? There will be talk of magic, of Madrid’s own sun king powers. There is no doubt that the Bernabéu will stretch you thin, will test your upstart nerve. Paris Saint-Germain collapsed under that gaze. Chelsea came here and won but somehow still lost, or lost just enough. That talk of light and heat seemed to tell the story in the moment. This was of course Madrid’s win more than City’s defeat, carried off with thrilling, nerveless precision. But the fact remains, it also raises some very difficult questions for Guardiola. Madrid will seek out your limitations, and will jump on them gleefully. This is what that rarefied air does to you. What they found in this City team wasn’t the standard errors of poor planning or bungled execution, but something more systemic, flaws built into the model. There is an annual spring pantomime around Guardiola’s team selection in this competition. What will he do? Will he jam a screwdriver into his own fusebox again? Or try to play the piano in a pair of boxing gloves? But there was none of that here. Guardiola picked his best team, and at times that best team looked like what it is, a beautifully fluid thing utterly committed to its patterns and rhythms. But there are limitations here too. Guardiola has been feted, rightly, as the best pure coach in the world. He misses nothing in preparation. He knows, to an unguessable depth of detail, the textures and patterns the rest of us simply watch from the sidelines. This is what makes his willingness to accept his team’s weaknesses so fascinating. Why didn’t City win? Because they kept on refusing to kick or head the ball into the goal, missing at least eight very good chances in a tie they lost by one goal. This is not bad luck or an off-day. This is profligacy by design. It is still startling that Guardiola’s squad doesn’t contain a single player whose chief skill, whose specialism, is scoring goals. And yes, City function so well as a team precisely because they don’t play with an orthodox striker. It is the overload in midfield that allows them to create all these chances in the first place. The system works. But pragmatism is also a strength, and that lack of cutting edge, of a one-punch knockout artist, while intellectually uninteresting to Guardiola, is a weakness in these moments. More prosaically, City’s players just looked tired on Wednesday night. The squad has depth, but not much. It feels like another part of Guardiola’s absolutism that the same core have tended to play most key games. The same refusal to bend was there in his use of his subs at the Bernabéu. Early on it seemed the story of the night might be Kyle Walker’s fine performance curtailing the menace of Vinícius Júnior. Instead City lost the game after Walker’s injury. Guardiola brought on Oleksandr Zinchenko to play left-back and swapped João Cancelo, rejigging both his full-backs in the cause of remaining decisively Pep. Bringing on Nathan Aké would have acknowledged this was a moment to contain and spoil, to spend 18 minutes damning up that side. Both of Madrid’s late goals came from those loosened flanks. It might seem perverse to find fault with a systems team playing like a systems team; to urge the current group of serial league champions to junk all that stuff and go for the throat. But knockout football at this level also takes you into these strange emotional spaces. A team that try to chase down the same perfect game every week will at times play cold when they need to play hot, just as City never really dug their teeth into this second leg. Perhaps that fragility is also a function of where the club has come from. It’s not an insult to state this City team is a construct. Guardiola’s success has been to install culture and method into something that is just over a decade old. It’s new-build, a prefab, an idea. No surprise, perhaps that it doesn’t bend with the wind like Real Madrid. For Guardiola the challenge now is to ensure his players are ready to chase the season to the end, when one slip in their remaining four league games could leave them with no trophy this season. Guardiola also has a shelf life. He has had six years now working in an environment tailored entirely to his wishes. It is no secret the Champions League, no matter how distant and how difficult, has always been the goal. The chief failing of Wednesday night is that it really didn’t feel any closer.