There is a question mark hanging over Kolo Toure's fitness for the trip to Old Trafford on Sunday.
The centre back injured his hip in the 2-1 win at Hamburg last night and was forced off after 29 minutes.
"It was a kick on the hip," said Arsène Wenger afterwards. "It looks like muscle damage.
"We do not know if he can play on Sunday [against Manchester United] at the moment. It is very difficult to say."
Arsenal.com hope to have an injury update later on Thursday
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