SIR Alex Ferguson is backing his young troops to exorcise the ghost of their Euro defeat and book United a Carling Cup semi-final spot tonight. Last Wednesday the Reds boss flooded his Champions League XI against Turkish side Besiktas with kids. But the new generation, who helped United win the League Cup last March at Wembley against tonight's Old Trafford opponents Tottenham, didn't gain their Euro spurs against the Turks. The 1-0 Group B defeat was condemned and the Reds starlets suffered heavy criticism. But Gabriel Obertan, Danny Welbeck, Federico Macheda and Darron Gibson are set to be told to carry on against Harry Redknapp's side in tonight's last-eight clash. "Those lads need to be challenged and I thought they did OK. They did not deserve that kind of criticism," said Sir Alex. "I don't need to motivate them with what has been said. Their future is well mapped out. But the one thing we cannot give them is an old head, which is what we saw in the last third of the pitch last week. "They got anxious. They created good chances and they hurried the thing. But that is not the biggest crime in the world. "We are not talking about ability. We are talking about experience and it is starting to stack up. That is why we have to play them. "We don't dismiss the Carling Cup," he added. "It has been an important competition for the younger players and lads on the fringes of the squad for many years. "Last year the lads went all the way to the final and won it, what a great achievement! "For people like Ben Foster, Jonny Evans and Darron Gibson to win their first trophy provided them experience which will stay with them for the rest of their careers. We have so many games that these players are an integral part of the squad. It is vitally important for them to go through the experiences they are now getting because ultimately it is going to make them better players.