Manchester United manager Sir Alex Ferguson is hoping either Rio Ferdinand or Edwin Van der Sar will be fit to face Liverpool on Sunday.
Defender Ferdinand is highly doubtful for the visit of the Reds to Old Trafford, having missed the last two matches with a back problem.
Meanwhile, veteran keeper Van der Sar is also struggling after being substituted with a recurrence of a groin injury in the FA Cup sixth round defeat to Portsmouth two weeks ago.
"We're waiting to see if Ferdinand trains this morning," revealed Ferguson at his pre-match press conference. "He and Edwin Van der Sar need to train to give me the confidence to play them.
"I'm doubtful over Ferdinand, but hopeful over Van der Sar. That would be a bonus really, having one of the two, given the experience of them."
Meanwhile, Ferguson expects Nemanja Vidic to play despite being substituted with a facial injury during Wednesday's 2-0 win over Bolton Wanderers.
Gerard Pique is expected to partner Vidic at the heart of the defence after deputising for Ferdinand in midweek, with Owen Hargreaves set to continue as a makeshift right-back.
"Vidic is okay, it's a nose knock," he continued. "He's had it twice in a row and he maybe needs it cauterized, but we'll wait until after the game.
"Pique did very well for me the other night, that's why I played him, and that's why I tried Owen Hargreaves at right-back. I'd be comfortable enough with that.
"Louis Saha got a knock on Wednesday, we'll have to wait and see what he's like. I thought he was okay yesterday, but it just flared up a little bit after training."