Per Mertesacker facing long injury lay-off

The German World Cup winner will be sidelined for "a few months".

Arsenal defender Per Mertesacker will be sidelined for "a few months" with a knee injury, manager Arsene Wenger has announced.

The 31-year-old suffered the injury in Friday's pre-season draw against Lens and did not travel with the rest of Arsenal's squad for their two-match tour of the United States.