Sir Alex Ferguson conceded Manchester United had performed poorly during their 3-0 Champions League semi-final second leg defeat to AC Milan.
Ferguson must now rally his team for Saturday's derby game
"Milan got their goals cheaply and that's disappointing," said Ferguson, whose side lost 5-3 on aggregate.
"They were sharper and quicker to the ball and I think they've been good winners. We were on the back foot all the time and found it difficult.
"In fairness, we never looked like we were going to score."
United's cause was not helped by some below-par performances from their star players, including Wayne Rooney, Ryan Giggs and Cristiano Ronaldo.
Of Ronaldo, United boss Ferguson admitted: "Cristiano had a disappointing night.
To play the way we did in the first half is a dream for a coach - it was perfect football
AC Milan coach Carlo Ancelotti
"He knows that but he is a young man and on nights like these he sees the professionalism and experience of AC Milan. It is good to see where he has to go."
Ferguson also rued the recent spate of injuries that has not allowed him to rest key players in the past few weeks.
"Milan were better prepared physically," he said. "They've been resting players and that can make a difference."
But Ferguson believes that his side will bounce back in Saturday's derby game against Manchester City, in which a victory - coupled with Chelsea failing to win at Arsenal on Sunday - would clinch the Premiership title for the Old Trafford club.
"You have to put disappointment behind you. We've handled it in the past and I'm sure they will handle it on Saturday," he said.
"They can win the title - we have to make sure they recover in the proper way."
AC Milan manager Carlo Ancelotti was "ecstatic" after Milan's comprehensive victory.
"It was an evening of dreams," he said. "To play the way we did in the first half is a dream for a coach - it was perfect football.
"The final will be a fascinating challenge - Liverpool are not as good as Manchester United but they are harder physically."