As Manchester City falter in Europe again, it’s clear Pep Guardiola’s defence needs rebuilding.
"This is the most difficult job I have ever faced," said Pep Guardiola soon after his arrival at Manchester City. After departing the Champions League before the semi-final stage for the first time in his managerial career, that much was confirmed.
Guardiola's side "were not there" for 45 minutes in Monaco and it cost them. The two-goal lead of the first leg was wiped out and while City did manage to restore the advantage after the break, their vulnerable defence was exposed once more soon after.
Much has been made of Guardiola's attack-first strategy but this is a coach who had prided himself on his defensive record. Jose Mourinho's Real Madrid had outscored him in Spain but it was Guardiola who had always boasted the best defence in every year of his career.
But he had not been coaching this particular Manchester City side.
There have been times this season when it has seemed as though Guardiola had cracked it. Eleven unbeaten prior to this defeat, City had scored 13 without reply on their travels with 10 clean sheets coming away from home. But in Monaco they just cracked.
Any semblance of solidity proved an illusion once more. When this defence is put under real pressure, the weaknesses reveal themselves and on this occasion Guardiola cannot merely bemoan the opponents taking an inordinate number of chances against them.
"We have conceded a lot of goals in Europe," he acknowledged afterwards. Sixteen of them, in fact. Only Legia Warsaw have let in more. And while the goalkeeper position has been a problem, it is worth noting that all but one quarter-finalists faced fewer shots on target.
This defence has just not been good enough to be considered elite.
Where Guardiola has been culpable is in not adjusting his plans to acknowledge that fact. While Craig Shakespeare has named the same Leicester line-up for three victories in a row, the City manager had not only never picked this team before but he sent out a back-four against Monaco that had only previously faced Sunderland (twice) this season. It showed.
The first occasion was in his opening game in charge and Guardiola has been fumbling for his best team ever since - reinventing on the fly in the hope of finding any real cohesion - but it seems the very best solutions are not within this squad.
One of the features of his success, particularly at Bayern Munich, was the incessant tactical tweaking. Philipp Lahm, for example, was sometimes asked to occupy multiple positions within one game. But that flexibility requires understanding that only comes with time.
Perhaps he has been guilty of showing too much faith in these players. He should have been aware that more protection would be required. And while Fernandinho's inclusion was explained as a tactic to cover the counter-attack, did it really need to be a choice between him and Yaya Toure? Why not give the Brazilian a partner there for added security?
Instead, at times it looked like a broken team with five defenders and five forwards. Given that City had a two-goal lead to defend, that was reckless, and the decision to switch Kevin De Bruyne to a deeper role after the break was an admission that he had got it wrong.
Put simply, Guardiola will not be able to press ahead with his plans for the future until the defensive half of this team has been overhauled. Five of the back six in Monaco are already over 30 and some of them are just not good enough to achieve the team's goals in Europe.
Changes at full-back, a position so important to Guardiola's system, are imperative and the brilliant Benjamin Mendy would not be the worst place to start. Meanwhile, the only thing more confusing than Aleksandar Kolarov's enduring presence at centre-back is the surprise when it does not work.
City will be inclined to trust in the vision of their coach and well they might given his track record. But this defeat was a reminder that Guardiola is a manager not a magician, a coach not a conjuror, and his talents do not guarantee a place among Europe's elite.
"I tried. And I will try again," he said. But not, one would suspect, with the same players.