Arsenal defender Thomas Vermaelen has undergone surgery on his left ankle and is expected to be out for at least six weeks.

Vermaelen underwent the surgery in Stockholm after suffering the injury in the Gunners’ 2-1 win over Udinese on August 24.

The Belgium defender, who missed eight months of last season with an Achilles injury on his right foot, will miss the North London derby at Tottenham on October 2 and the club’s first two Champions League group stage matches.

An Arsenal statement read: “Vermaelen has undergone a minor procedure to remove an inflamed plantaris tendon from his left ankle. This is the same treatment that he had on his right ankle in January this year and has nothing to do with his Achilles tendon.”