Wayne Rooney will miss Manchester United's Champions League clash with Valencia on Wednesday.

Sir Alex Ferguson has told club officials the 24-year-old will not be fit enough to make the trip after being withdrawn with an ankle injury against Bolton on Sunday.

There has been no indication whether Rooney's absence will be any longer, which would threaten his participation in Saturday's Barclays Premier League encounter with Sunderland at the Stadium of Light, plus England's Euro 2012 qualifier with Montenegro on October 12.

While Ferguson's assistant Mike Phelan revealed Rooney is still struggling with a niggling ankle injury, some may feel it is a good time for Rooney to have a break.

On ESPN on Sunday, Kevin Keegan voiced his concern for the striker, who has scored only one goal for United this season, and that came from the penalty spot.

Although the furore over his private life has hardly helped, Rooney was so ineffective against Bolton that purely on form grounds Ferguson might have looked at a combination of Dimitar Berbatov and Michael Owen against Valencia anyway.

Now Rooney can have a couple of days away from the glare of publicity and try to get himself into the right frame of mind for when he next plays.

Meanwhile, skipper Nemanja Vidic has told his team-mates to cut out the defensive lapses that are wrecking their Premier League title campaign.

Defeats for Chelsea and Arsenal on Saturday should have been the start of a perfect weekend for United, who would have moved to within a point of Carlo Ancelotti's men if they had beaten Bolton.

Instead, the problems which are proving so difficult to eradicate reared their heads again.

A combination of slack marking by Jonny Evans and Patrice Evra moving away from the post he was supposed to be defending allowed Zat Knight to put Bolton ahead.

Then, after Nani had scored a brilliant equaliser, the visitors offered Martin Petrov far too much room to exhibit his talents as he cut inside Park Ji-sung to drive a second goal beyond Edwin van der Sar.

In the end, United were lucky to have the chance of settling for a point as Johan Elmander blasted a brilliant opportunity over the crossbar which surely would have given Bolton victory.

Owen's third goal in a week ensured United did not make the short journey back down the M61 empty-handed, but the brutal truth is that they have now conceded nine goals in five Premier League games.

Even basement boys Everton have done better than that, while Ferguson's men are still to record an away win in three attempts.

"It is a big concern that we are conceding so many away goals," said Vidic.

"We have to stop doing it. We cannot let it happen again."

It hardly seems believable that the same defenders responsible for the present malaise should concede just 22 and 24 goals respectively during the entire Premier League title-winning campaigns of 2008 and 2009.

Rio Ferdinand's absence is clearly not helping but the England skipper was also missing when United went 14 games without conceding a goal during the mid-winter of the 2008-09 campaign that also included a trip to Japan for the Club World Cup.

As the man who now wears the captain's armband, Vidic feels the responsibility more than most.

"Over the last few years we haven't given that many goals away or even allowed them so many chances," he said.

"Before we have always looked strong, so this is not what we are used to.

"We have to play much better in our away games."