Sir Alex Ferguson admitted his Manchester United side could "have been two or three down" as he reflected on their poor start to a night that ultimately ended in huge satisfaction for the Premier League champions.
"The first goal, with the deflection, was a bad goal for us and it took 15 to 20 minutes for us to get our composure back," the United manager said. "Oh God, it was a catalogue of mistakes. That first 20 was a bad period for us. We could have lost a few goals. It was a good start for them and took us a long time to get going. I don't think we deserved to be level at half-time but we were, and in the second half we were fantastic."
Ferguson identified Paul Scholes's equaliser late in the first half as the moment the game swung in United's favour but warned that his team "could not think for one minute" that their place in the quarter-finals was guaranteed. "A game of football always carries risks and the important thing for us is to play at our level. We are going to try to win the match at Old Trafford."
There was, however, a sense that Milan had blown their opportunity considering the number of chances they had to increase their lead when the score was 1-0. "We did really well in the first half and if we had taken our chances, it would have been a different game," said David Beckham, who played for 72 minutes before being substituted. "The thing is that when you play against a team like Manchester United, you have to score the goals when you have the chances."
Ferguson went on to acknowledge that Ronaldinho had shown he was "back to his best" and admitted that Rafael had found the former world footballer of the year a "difficult handful". He added: "The reason I played him was quite simple, namely that we have invested in a great future and we were not going to stop the rewards of that because we were playing AC Milan.
"He has to learn, against Ronaldinho, that this is the real world. He [Rafael] made some mistakes, but he won't make them next season. He will eradicate those mistakes because the boy is an outstanding talent."
The downside for United came in the form of Michael Carrick's red card. "Michael was sent off for apparently wasting time," Ferguson said. "I didn't notice it at the time and I thought he was booking [Patrice] Evra. It is unfortunate. It is one of those soft sending-offs that has left the referee with no option. He [Carrick] was just rolling the ball away, but it has been deemed he was wasting time."
An injury to Pato took the gloss off AC Milan's 3-1 victory over Atalanta with the Brazilian striker now facing an anxious race against time to be fit for the Champions League return leg against Manchester United.
The forward produced a neat turn and finish on the half hour before converting Ronaldinho's pass 11 minutes later. Jaime Valdes netted for the visitors after the interval but Marco Borriello was quick to restore Milan's two-goal advantage after Ronaldinho's penalty was saved.
"We will have to wait 24 to 48 hours before knowing the extent of the injury,'' said Milan vice-president Adriano Galliani after the game. Milan must overturn a 3-2 deficit if they are to progress to the quarter-finals of the Champions League.
"Not to have Pato would be terrible,'' said Galliani. "We don't have anyone who can replace him. Without him, we would need to change our tactical set-up.''