Danny Welbeck
Danny Welbeck has not played since April due to a knee injuryGetty Images

Arsenal's failure to sign a striker during the summer transfer window will come under more scrutiny following the announcement that Danny Welbeck will miss months of action after undergoing knee surgery.

The former Manchester United striker has not played in four months, and was dogged by a knee problem throughout the summer. Despite Arsene Wenger initially suggesting the forward could return for the Emirates Cup during their pre-season campaign, he now looks set for a lengthy lay-off.

Bewilderingly, the club state the decision for Welbeck to undergo surgery was taken last week, when the transfer window was still open. A statement from Arsenal read: "Danny Welbeck has undergone surgery on his left knee after being unable to sufficiently step up his rehabilitation work.

"The striker has been working throughout the summer to recover from the injury sustained at the end of April. It had been hoped he would avoid surgery but, after increasing his training workload, the injury to his cartilage did not respond as well as hoped. The decision was taken last week for him to undergo surgery by a leading specialist in the field. Danny is now expected to be out for a period of months and everyone at Arsenal wishes him well."

Arsenal have struggled in front of goal this season, finding the back of the net themselves just once, with wins over Crystal Palace and Newcastle United coming via own goals. That struggle heightened calls for the club to bring in an established centre forward but Tuesday's transfer deadline passed without any activity.

The Gunners are the only Premier League side not to have added an outfield player to their squad, with Petr Cech the sole addition in goal.