Rising Lyon star Nabil Fekir faces a long spell on the sidelines after rupturing his right knee ligaments playing for France in a friendly against Portugal on Friday.
The French Football Federation confirmed the injury, calling it ''terrible news.''
The 22-year-old Fekir was voted the French league's best young player after scoring 13 league goals for Lyon last season.
A technically gifted and mobile forward, he scored four goals in four games this season and his hat trick away to Caen last weekend earned him a first start for France in Lisbon.
After just 14 minutes, he twisted his knee when under no apparent pressure and was replaced by Atletico Madrid forward Antoine Griezmann.
Lyon president Jean-Michel Aulas tweeted ''my thoughts are with Nabil, who is stronger than you imagine.''