Jonny Evans missed United's 2-1 success against Liverpool due to a hamstring problem.
The Northern Ireland international has been in splendid form all season but had to watch from the sidelines as Rio Ferdinand and Nemanja Vidic started the keenly-contested victory.
Vidic went off towards the end of the game with what appeared to be a knee injury, with Chris Smalling replacing the skipper for the closing stages.
Sir Alex Ferguson will now assess his troops ahead of Wednesday's FA Cup third-round replay with West Ham at Old Trafford.
"Jonny Evans felt his hamstring yesterday afternoon," he informed MUTV. "I was at Nottingham [watching Forest v Peterborough] and got a message at half-time. He trained in the morning so it was strange. But Vidic and Ferdinand are experienced and you can't say any more than that. They were brilliant."
Meanwhile, Anders Lindegaard was ruled out of Sunday's clash with 'flu, so young stopper Ben Amos was on the bench.