The Portuguese winger missed the Reds' Boxing Day victory over Sunderland with a hip injury, but Sir Alex Ferguson confirmed post-match that he may return against Alex McLeish's side.
"Nani's been feeling his hip a little bit in the last couple of days, so we left him out," the boss told MUTV. "I think he should be ready for the Birmingham game. Fletcher had a bit of a cold, he came down with it this morning and we couldn't take any chances with it."
Alex McLeish's side have gone over a fortnight without a match, following the postponement of their games against Newcastle and Everton. Going up against a fresh side who have suffered just one home defeat all season, Sir Alex is mindful of the task facing his side.
"They'll be fresh and going down there's always a difficult place to go to," he admitted. "They've got a strong home record and they're difficult to beat on their own ground. We're well aware of that and hopefully we can get the players fresh, give them their recovery tomorrow and make maybe a couple of changes to freshen that part up and hopefully we can get the result we want."