Marseille were dealt a severe blow on Saturday when highly promising defender Cesar Azpilicueta was ruled out for the rest of the season.
The 21-year-old Spaniard's campaign was cut short after he ruptured his anterior cruciate ligaments in his left knee during the early stages of the French champions' 4-0 Ligue 1 win over Montpellier.
Coach Didier Deschamps voiced his sympathy for Azpilicueta, who has gradually improved since arriving at the Stade Velodrome from Osasuna in the summer.
"His season is over," confirmed Deschamps. "It's a huge black mark. We are really disappointed for him, especially as he was in top form.
"It is a very sad moment for him, who is a young player of 21 years of age and full of self belief."
Deschamps, who guided Marseille to the last 16 of the UEFA Champions League for the first time since the 1999-2000 season earlier this week, is weighing up whether or not to replace the young Spaniard right away.
He has just one direct replacement in the shape of Charles Kabore.
Deschamps added: "We could try and bring one in immediately, or we could take a small risk and wait for the transfer window in January."