Cruyff said: "I am convinced it will be a great day for Barcelona.
"If they lose, they have nothing left to play for this season but I don't think that will be the case.
"They can't afford to let their season drift away and this should motivate them. At Old Trafford there is no favourite for the game.
"As long as Barcelona impose their style on United early on and create space then I'm convinced they will win."