Ankle operation for Mertesacker

Arsenal defender Per Mertesacker has undergone surgery on his ankle injury and will be out "long term", according to manager Arsene Wenger.

Mertesacker suffered ligament damage during Saturday's 2-1 victory at Sunderland and could be sidelined for the rest of the season.

"Unfortunately he has had surgery and we have lost him for a while," Wenger told the club's official website, www.arsenal.com. "How long I don't know. He had reconstruction of his ligaments, so it will be long term."

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