Arsenal midfielder Samir Nasri has suffered a broken leg during the club's pre-season training camp in Austria.
The France international is facing between two and three months on the sidelines after fracturing his right fibula on Tuesday morning.
Nasri will miss the opening weeks of the Premier League season and will be hoping to return to action at some stage in October.
The 22-year-old suffered the injury during a training match at Arsenal's summer camp in Bad Waltersdorf and was immediately taken to a nearby hospital.
A statement on the club's official website confirmed: "Samir Nasri has sustained a fractured fibula during this morning's training session at the club's pre-season training camp in Austria.
"The midfielder will be out of action for two to three months."
The news will come as a major setback to Gunners boss Arsene Wenger as he looks to end the club's four-year trophy drought.
On top of missing several weeks of club action, Nasri has been ruled out of France's forthcoming World Cup qualifiers against Faroe Islands, Romania and Serbia.