New signing Nacho Monreal could go straight into the Arsenal side for the game against Stoke in the Barclays Premier League.
The Gunners moved to push through a deadline-day deal for the full-back after Kieran Gibbs was ruled out for up to six weeks with a thigh problem.
``Our scouts have followed his progress for a while and of course we had a blow with the Gibbs injury, which is a bit longer than expected,'' said manager Arsene Wenger.
``We expected two to three weeks, now it will be four to six, so we were in a position where we had to make a quick decision. That explains our buy.
``I believe we need two left-backs. You cannot play every single game with the same player. We had two before, we have two again now.
``We believe he can integrate our style of play and adapt very quickly to that.
``He has the characteristics to play our game because he is very mobile, has a good left foot and is very good in combination play. It is of course vital in our style of play.''
Centre-back Thomas Vermaelen (ankle) is a doubt, but midfielder Mikel Arteta may return after his calf injury.
Francis Coquelin (hamstring) is sidelined and forward Gervinho is away at the African Nations Cup.
Stoke made two new signings on deadline day, goalkeeper Jack Butland and winger Brek Shea - but neither will be involved in the short term.
Butland has been loaned back to Birmingham and USA international Shea is still recovering from a foot operation.
Assistant boss Dave Kemp said: ``We've brought in two excellent young players but they are both for the future.
``To be honest, the squad is unbalanced. We've been aware of that since the summer. We tried to correct it in the last window and didn't manage it, and the plan was to get through to this window and address it and unfortunately we haven't.
``In each window, I think the way football's gone now you have to keep freshening the squad up. We didn't do it this time last year, and I felt we suffered for that a bit, we did in the summer window but we've missed the boat again a little bit.''