Sir Alex Ferguson enjoying Fulham's equaliser on Saturday

Alex Ferguson is in a sweat over Manchester United’s star strikers.

He fears Ruud van Nistelrooy is suffering from burn-out, while Louis Saha’s heel injury has left him limping ahead of their FA Cup Quarter Final against Fulham and their Champions League return against Porto.

Van Nistelrooy was dropped for last Saturday’s 1-1 draw at Fulham. And boss Ferguson admitted: “Ruud said he did not feel sharp in the first leg against Porto. So I decided on a bit of freshness up front on Saturday.

“Ruud has carried the burden up front a long while. It is time we looked at that.”

Saha can rest before the Porto game as he is cup-tied for this weekend’s Fulham clash.