Marseille will be without Senegal central defender Souleymane Diawara for the remainder of the season due to a knee injury.
The 33-year-old suffered a serious sprain with a tear of a back cruciate ligament in Saturday's 1-1 draw with Nice.
Tests conducted by the club's medical staff on Sunday morning "revealed signs of a serious knee sprain with torn anterior cruciate ligaments".
Marseille have now confirmed Diawara has been booked in for season-ending surgery next week, meaning a six-month absence.
"He will undergo surgery next week. He will be out of action for about six months," the club said on their official website.
Diawara was already scheduled to miss Wednesday's UEFA Champions League quarter-final first leg against Bayern Munich because of suspension.