Summer signings Robin van Persie and Shinji Kagawa are fit for the Barclays Premier League visit of Wigan Athletic on Saturday, but Phil Jones could be sidelined for up to 10 more weeks.
There was speculation that van Persie and Kagawa could miss the game after picking up strains on international duty in midweek, but Sir Alex confirmed at his Friday press conference they will be available to face the Latics.
The news is not so good for Jones, who recently underwent surgery on a knee injury sustained in training, but Chris Smalling is not far off a return to action. Meanwhile, Darren Fletcher has been included in the squad as he continues to make good progress in managing his ulcerative colitis condition.
Sir Alex did not refer to Wayne Rooney in the first part of his press conference, but the striker was expected to be out for four weeks when he was injured against Fulham on 25 August.
"On the injury front, everyone's fit, apart from the ones we know about – Jones and Smalling," said Sir Alex.
"Jones was a bad blow for us. He got an injury in training last weekend and he'll be out for eight to 10 weeks.
"We expect Smalling to be back training by the end of the month. There's a little bit of comfort in that sense, given our centre-back situation. But with Jonny [Evans] back we're in a better position than we were a couple of weeks ago.
"Darren's in the squad tomorrow, simply because I think it will give him a boost. It's a chance to progress. At this moment in time everything's going fine for him."