Fabregas has been suffering with a hamstring problem over recent weeks, but he could benefit from the extra couple of days' rest as the Gunners prepare to travel to Old Trafford on Monday.
The Arsenal skipper was initially expected to miss the fixture, but Wenger revealed on Thursday that he will put Fabregas through a late fitness test.
"We could have Cesc Fabregas [back]," said Wenger on Arsenal's official website. "But there is a big uncertainty if he can be in the squad or not. That will be decided very late."
While Fabregas will not take any risks in rushing back too soon, the Arsenal skipper remains positive he could face United. "Training, training and more training. Hopefully I'll be available for Monday,'' he wrote on his personal Twitter account.
Meanwhile, Kieran Gibbs is definitely out of the United fixture, after Wenger revealed the defender will be absent for three weeks. Gibbs twisted nastily on an ankle during Arsenal's 3-1 Champions League victory over Partizan Belgrade, and was withdrawn for Emmanuel Eboue prior to half-time.
"We have lost Kieran Gibbs from Wednesday night but he should be the only one. We think today that he will be out for three weeks," confirmed Wenger. "I am very disappointed. I hope it will not put in his mind that he is an injured player. It was just an accident and you cannot do anything about it. Time will help him get over that and it is not major damage in his ankle.
"We should have Gael Clichy back. He was in today. He was very weak still but we hope he will progress well. We could have Johan Djourou available for Monday night. He should be fine."