Sir Alex Ferguson says he can understand Carlos Tevez's frustration at not being a regular member of his Manchester United starting line-up.

Tevez has been the odd man out since Dimitar Berbatov's arrival at Old Trafford, with speculation mounting that he may opt not to turn his loan deal into a permanent United contract when the season reaches its end next May.

However, Tevez scored four goals in the midweek Carling Cup victory over Blackburn to leave Ferguson with a major selection dilemma for tomorrow's meeting with Sunderland.

"It is obvious Carlos doesn't enjoy it," Ferguson said. "He wants to play. But do I want players who are quite happy to sit in the stand?

"I have to manage that situation the best I can. I understand he wants to play. I want to pick a team that wins. I have to be as fair as I possibly can. Performances do matter and his performance on Wednesday gives me a big problem.

"I have been doodling on my pad trying to see how I could fit all these players in, but one of the important parts of your team is a proper balance. I am working on that.

"It was a fantastic performance from the lad on Wednesday, full of energy and aggressive running. The lad always tries and I admire him for that, even if it does not make my job any easier."

Ferguson acknowledged there were other eye-catching displays as United sealed their place in the Carling Cup semi-finals.

Anderson was outstanding in central midfield, while Jonny Evans and Ben Foster were among the stand-out performers at the back. With five trophies to play for over the coming months, Ferguson is confident that his squad can handle the demands of a congested fixture list.

"There were a lot of good performances on Wednesday, which tells me I have a good squad and gives me encouragement that we will be able to handle these fixtures in the second half of the season," he said. "We have two games to make up once we have come back from the Club World Cup in Japan but we have lost two midweek dates due to the Carling Cup semi-finals.

"If we were to get to the final it would be another game, so you can understand our concerns a little bit. The squad that played on Wednesday will be the one I use in the semi-final. That is for definite."