Timber has recovered from an ACL injury suffered in the opening game of the season and is now taking part in full-scale training.
Speaking yesterday, Gunners boss Mikel Arteta said: "He's doing very well, he's back training. He's not far off, but the thing is that last step, he hasn't played any minutes so does he need a game with the U21s, does he need two games?
Advertisement
Advertisement
"We are going to have to see, especially because he's training with us and we need to see how long that will take him. That last part is tricky and sometimes takes a while. Hopefully, he'll be back as soon as possible."
Arsenal meet Stoke City U21s on Monday.