Sir Alex Ferguson has admitted he got it wrong in expressing fears Dimitar Berbatov was struggling with his knee injury again. Berbatov scored the opening goal in Manchester United's 3-0 win over Burnley at Old Trafford on Saturday but was substituted before the end and headed straight down the tunnel for treatment. Immediately after the game Ferguson claimed his £30.75million record signing had suffered a recurrence of a knee injury which he has been advised to have an exploratory operation on. In fact, the former Tottenham star had only suffered a dead leg and while he is a doubt for Tuesday night's Carling Cup semi-final first leg at Manchester City, he has not completely been ruled out. "I thought Dimitar had got a knock on the knee. It turned out it was a dead leg and we are having a look at that it. "I am hoping he will be all right but he is a doubt and we will see what he is like in the morning." Ferguson also confirmed Ryan Giggs would not be considered, and neither will Rio Ferdinand, even though the England star is continuing to edge closer to a comeback after three months out with a back injury. "Rio is training quite well now," he said. "He is a lot closer now but he is not in contention for Tuesday." However, the United boss is considering whether to add a bit of youth to his team in the form of Darron Gibson and the Da Silva twins Rafael and Fabio. Having already absolved the younger members of his side from blame for the shock home FA Cup defeat by Leeds, Ferguson would have no qualms about putting them into such a high pressure encounter. But it does seem the United boss intends to select a far stronger team than the one he originally intended when the draw was made last month. "I have got to think about getting a mix in terms of the programme we have got and also the fact I have given young players a game in the past," he said. "I will have a strongish team but there will be some young players as well." Which team should Ferguson send out? Have your say.