Mustafi appeared to pull his thigh muscle in the build up to Azerbaijan's equalising goal in the first half.

He was carried off and replaced by Matthias Ginter.

Mustafi will undergo scans and tests on his return to north London.

Arsenal travel to Watford on Saturday and he is likely to miss the Vicarage Road clash.

It is a big blow for Arsene Wenger, who lost Laurent Koscielny to an Achilles problem before this international break.

Arsenal were willing to let Mustafi leave during the summer transfer window and he started the season on the fringes of the first team.

But he has forced his way back into Wenger's plans, starting the last four Premier League games.

Arsenal have not conceded a goal during that run.

Per Mertesacker is likely to return to the team in Mustafi’s absence, alongside Rob Holding and Nacho Monreal.