Roy Keane has delivered a typically blunt assessment of another failed Manchester United Champions League campaign. The United captain could not have worked harder to inspire his team to victory over AC Milan.

But after a pair of Hernan Crespo match-winners shepherded United out of the competition at the first knock-out stage for the second season running, Keane, who it is looking increasingly likely will never have the chance to grace a European Cup final, was left nursing a deep sense of underachievement.

"The last 16 is no good to anybody, is it?," he said. "We live with the expectation. That is part and parcel of playing for a great club. Losing a game such as this is obviously disappointing for the manager, the staff and the players. But if you don't score in two games, you don't deserve to go through do you?"

For once Keane, the epitome of the never-say-die attitude that has characterised United under Alex Ferguson, opted not to publicly lambast sections of his team.

There appeared to be no simmering sense of injustice, more an uncomfortable acceptance that this United side just may not be good enough. Not only did the Old Trafford outfit fail to score in a two-legged European tie for the first time since Borussia Dortmund knocked them out at the semi-final stage in 1997, in 180 minutes, they also failed to force Milan goalkeeper Dida into a single meaningful save.

"There were 11 of us out there and we all have to look at each other," said Keane. "We had a few half-chances and in a tight game you need to take them - we didn't, they did. It would have been nice to play better but the aspect which is more disappointing than not scoring the goals we wanted is that we didn't test their 'keeper a bit more."

Ferguson and his team have reason to bemoan the luck of a draw that pitched them into combat with a side that could easily lift the trophy in May.

Some may argue if United had taken their final group game against Fenerbahce more seriously, they would have qualified in top spot instead of Lyon and secured the kind of easy passage to the quarter-finals the French champions enjoyed with their 10-2 aggregate win over Werder Bremen.

As Ferguson would no doubt point out, United could just as easily have landed Barcelona, Bayern Munich or Real Madrid all of whom could have been expected to take maximum advantage of Roy Carroll's first-leg blunder which proved so crucial in the overall outcome.

And, as United set their sights on a face-saving FA Cup mission at Southampton on Saturday, it is those basic errors that need to be eradicated if they are to ever have a chance of emulating their 1999 Champions League triumph.

Three cup exits on the trot, against Chelsea in the League Cup, FC Porto in last season's Champions League and AC Milan this time around, can be traced directly to goalkeeping errors.

Against top opposition, when chances in a two-legged tie can be counted on the fingers of one hand, you cannot get away with gifting goals to the opposition.

"It is a fine line," said Keane. "In any top game you need to take your chances, which is what Crespo has done. We have some very good younger players at this club. They will be better for the experience next year."

At 33 there are not that many next years left for Keane, who does not class himself a European Cup winner because he was suspended for the victory over Bayern Munich even though he was awarded a medal.

So, though he has four triumphs in the FA Cup already, he will be leading from the front as United try to secure a semi-final spot this weekend. "We will look to bounce back from this. Showing character is what it is all about."