Manchester United boss Sir Alex Ferguson intends to buy this summer.
If they fail to overhaul Carlo Ancelotti's Chelsea, it means Ferguson's men could end up with just the Carling Cup for their efforts.
Ferguson said: "When you are challenging for four trophies it can have a draining effect. You have to be aware of that and spot the moment when it is time to freshen up one or two players. The demands and pressures on players can be exacting."