Danny Welbeck has taken part in Arsenal training for the first time since April following surgery on his left knee.
Welbeck is not expected to play a competitive match for the first-team until mid-February but may make his return to action with the Under-21s next week.
"Danny has not played since April 2015 and we are now in February basically, so that is very long for a top-level competitor," said boss Arsene Wenger.
"You have to accept that he goes through small steps and one of them is to play in the under-21s, first for 45 minutes.
"He is basically fit but now it is to absorb the competition and the intensity of the competition. That is the next step for him."