Ninety minutes of control, an hour and a half of pressure, ultimately proved worthless. A goal less than a minute from the first whistle and a goal less than a minute from the last cost Barcelona victory as they began their defence of the European Cup.
Alexander Pato had scored the opening goal in the opening minute but Barcelona had turned the game round in style. Then, just when it looked as if their work was done, they threw it away again. Pedro and David Villa gave Barcelona a 2-1 lead but in the final minute a Milan side that had barely ventured out of their half were level when a Clarence Seedorf corner was headed in by Thiago Silva to make it 2-2.
Pep Guardiola said: "There is not much I can say: sometimes things like this happen. We had a lot of possession, we generated a lot of moves, but that wasn't enough to win this time. But I think we played very well; we moved the ball from left to right; we got in from the second line."
The Barcelona coach added: "But Europe is like that – against big teams this can happen. We still have five games; we'll see what happens. I am not worried. From the first minute to the 92nd, we were the better team. The fact that no team has won this competition two years running shows just how hard it is to win this. You see that Manchester United gets to three finals in four years and can't do it – that is indicative of just how hard it is. There are great teams in the Champions League."
Barcelona may reflect that the game had proved irrelevant; the Milan goals that were its bookends had not. And yet Barcelona were delivered a warning here. There was, after all, something not entirely unexpected about the way that the win slipped away from them. The decision not to sign a centre-back in the summer may yet be one they regret – not least because the man who headed in the winner had publicly admitted to being one of the Catalans' targets.
If the night ended badly, it had not started well either. Only 25 seconds had gone when the champions were trailing, the ball sitting in their net almost before they realised the campaign had begun. Alexander Pato knocked the ball between Barcelona's two centre-backs, positioned virtually on the half-way line, and dashed beyond them into a huge expanse of space behind. Faced by Victor Valdes, he slotted the ball easily home, low and centrally into the net.
It was the fifth fastest goal in the history of the competition and, in truth, centre-backs may not be the most appropriate of titles for the men Pato had so effectively split. With Gerard Piqué injured, Barcelona had at least expected Carles Puyol to make a return. Instead the club captain, absent on each of the six occasions that the European champions lost last season, was on the bench, not introduced until midway through the second half. That meant two central midfielders, Sergio Busquets and Javier Mascherano, at centre-back, with Seydou Keita as the deep-lying midfielder theoretically protecting them.
Barcelona had started with 10 of the 11 who defeated Manchester United at Wembley but Piqué's absence is significant and Keita needed to protect Busquets and Mascherano, jabbing in a toe to take the ball away from Pato as he raced through again 15 minutes later. Despite that intervention, the role of pivot is not Keita's best and, although Barcelona settled into control of possession, racking up 70% by half-time as they probed for a way through, they looked vulnerable when Milan sprang forward from the deep position they took up on the edge of their area.
Pato's speed was simply too much for Mascherano and Busquets and soon Guardiola was asking Eric Abidal to come across to a more central defensive position and cover the Brazilian. Busquets shifted too, stepping into a more natural central midfield position.
At the other end, with Lionel Messi dropping deep and constantly involved, chances came Barcelona's way. David Villa hit the side-netting and struck an acrobatic volley over; Christian Abbiati twice pushed Messi shots wide of the post and watched as the Argentinian thumped a curling free-kick off a post. He was then quickly down to his left to smother another Messi shot, this time from the top left corner of the area.
Messi was not to be denied. Just after the half-hour he collected on the edge of the penalty area again and dashed left through the smallest of gaps. He appeared to have knocked the ball too far ahead but a sudden surge of pace took him past Ignazio Abate and Alessandro Nesta, suspended in space by the speed of it all. And with the slightest of touches, almost cutting across the side of the ball, Messi smuggled it across the six-yard box. Pedro, screeching in on the far post, could hardly miss.
Andrés Iniesta was forced off with a muscle tear but in replacing him with Cesc Fábregas Barcelona lost nothing; their control became total and they could have been 2-1 up just before half time when Dani Alves's wonderful angled pass through the legs of Gianluca Zambrotta and Messi stepped expertly around Abbiati on the byline, only to see the linesman's flag raised. The decision was tight indeed.
If that decision went against Barcelona, the next did not. Four minutes into the second half Antonio Cassano nudged Busquets over. There did not appear to be a huge amount of contact but it was sufficient for Martin Atkinson to blow. David Villa hammered a 30-yard free-kick curling and dipping over the wall and into the top corner, away from Abbiati's right-hand. Milan's resistance was broken. Barcelona had been chipping away at it from the 25th second. There was still something left, though. And as the clock ticked away, there was still a corner to be taken too.