Ole Gunnar Solskjaer faces a spell on the sidelines after limping off during Manchester United's 1-0 defeat to FC Copenhagen last night.
The Norwegian sustained a hamstring injury in the final minute of the Champions League game which is set to rule him out for "a few weeks", according to manger Alex Ferguson.
"It's unfortunate for Ole," he said. "It is a hamstring and he will be out for a few weeks. But I am actually quite happy.
"Given his previous history of knee problems, I was a bit concerned when he came off but, fortunately, it is only a hamstring."
Solskjaer's absence meant United finished the game with 10 men and the loss means they have still to qualify from the group.
United are also set to be without Gary Neville (calf) and Ryan Giggs (hamstring) for Saturday's home Premiership clash with Portsmouth.
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