Barcelona have made yet more Champions League history, becoming the first team in the competition's history to concede a two-goal first-leg deficit and then come through the tie without conceding in the return match.
Lionel Messi scored a brace within 40 minutes, with David Villa and Jordi Alba adding to the scoreline after half time. After the match, assistant manager Jordi Roura said the critics have now been proven wrong.
"We're happy, we're satisfied and we're still in the Champions League," he said, according to the Guardian.
"Some of the criticism of the team was over the top. It was exaggerated. We were not so bad before.
"Tonight, Milan struggled to get into the game, especially in the first 20 minutes, but I would not talk about things that Milan did wrong; I would talk about the attitude of Barcelona, about how they pressured and worked.
"They made it look like Milan did things wrong but it was more that we did things right.
"If there is one thing that surprises me about the players, one thing I have learned, it is that they are so competitive despite having won it all.
"These are players who really feel it, who hurt when the team loses, and that is one of the reasons why they are so good. These have been hard times but they were extraordinary. They have a voracious appetite."
On Messi, Roura said: "He gave another magisterial lesson in how to play football. He has shown once again that he is extraordinary and that on the big occasions, surrounded by great players, he can do amazing things."
Meanwhile,Villa insisted that the spirit of the old Barcelona, who have won the Champions League twice in the last four years, has returned to the side as they look to lift the trophy again.
"When you go through that, the bad days are forgotten," he explained. "We do not care who we get in the quarter-finals."