Lyon midfielder Clement Grenier has been ruled out for up to four months after picking up a thigh injury during the pre-season Emirates Cup at Arsenal.
The 24-year-old sustained the non-contact injury during the French side's 6-0 thrashing at the hands of the Gunners at the Emirates Stadium last weekend.
A statement from the club said: "Injured last Saturday during the friendly match against Arsenal, Clement Grenier has suffered a complete rupture of the rectus femoris tendon of the left leg.
"After consultation with president Jean-Michel Aulas and Dr Emmanuel Orhant, Clement decided to have surgery by Dr Bertrand Cottet-Sonnery.
"The operation will take place Friday at the Jean Mermoz Private Hospital in Lyon. His unavailability is estimated at four months."
Grenier struggled with groin and thigh problems last season, managing just seven appearances for Lyon.