The German picked up a hamstring injury against Fenerbahce while the Gunners also saw two key central midfielders pick up knocks, but who would be the biggest loss?
Arsenal are facing the prospect of going into the North London derby without Lukas Podolski, Jack Wilshere or Aaron Ramsey.
The Germany attacker, who scored a double against Fulham at the weekend, went off with a hamstring injury against Fenerbahce and is expected to be out for three weeks.
Ramsey scored three times over the two legs to help secure Arsenal's passage to the group stage for the 16th consecutive season but suffered a knock.
Wilshere was also a victim of the Turkish side's tough tackling late on, but finished the game despite looking visibly hurt.
With the match against Tottenham looming on Sunday, three new injuries are the last thing Arsene Wenger needed after a summer of frustration in the transfer market.
Which member of the trio would be missed the most? Can Podolski's goals be replaced? Do Arsenal have competent replacements for Ramsey and Wilshere?
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