Kaka's solo goal in extra time finally separated the sides after a goalless first leg at Celtic Park and 90 more minutes where both defences held out.

The 24-year-old Brazilian said: "I am really happy with the contribution I have made to the team.

"It was a difficult game, really difficult and we are worn out.

"Celtic showed lots of maturity and tried to play their game but in the end we scored because we deserved it.

"I think overall we were the better side."

Gordon Strachan insisted he was "very proud" of Celtic after their Champions League dreams were shattered in Milan.

Until Kaka's brilliant goal Celtic had bravely, and a little fortunately, withstood increasingly heavy pressure from the home side.

However they had a good call for an early penalty when Paolo Maldini clearly committed a handball offence, and Shunsuke Nakamura also thought he should have had a spot-kick after going down under a clumsy challenge in the second half.

"(It was a) fantastic evening," said Strachan. "What a great stadium, great atmosphere and two teams - one with a bit more technique, one with incredible heart, will and determination.

"If we can improve on technique we'll be a good side. That's the vision.

"We've got an incredible will to win.

"I'm very proud of them. If there was a Champions League trophy for guts and determination then we must be in with a chance of winning it."

Strachan refused to discuss the penalty appeals.

"I don't want to sour the night with headlines about referees," he told the after-match press conference, broadcast by BBC Radio Scotland.

"The night belongs to the players who played the game and supporters of both sides. I'll leave the rest for everyone to get on with."

Strachan insisted that Celtic felt the tie was winnable.

"They did believe, all the way through it, that they could get a goal."

Strachan expects his players to be stronger after experiencing the Champions League knockout stages for the first time.

"They know now if we do improve our technical level they can be a match for anybody," said the Celtic manager.

"We've enjoyed the experience and I think they've enjoyed the night, until the final whistle blew."