Marseille's Valbuena ruled out for 10-12 days
"Mathieu Valbuena felt a pain on Wednesday and a scan showed that he had a groin injury. He will be out for 10-12 days," OM said on their website.
Marseille are second in the standings with 54 points from 30 games, seven points adrift of leaders Paris Saint-Germain.
They take on Girondins Bordeaux on Friday.