Bakari Kone scored the decisive goal as Marseille survived a late scare to record a hard-earned 2-1 win against Sochaux and move to the top of Ligue 1.
Kone's second-half strike added to Karim Ziani's opener to give the Mediterranean side a seemingly unassailable lead.
However, Sochaux mounted a late comeback when Mevlut Erdinc reduced the deficit in the 72nd minute with a controversial goal to set up a nervy finish.
Sochaux started slowly, but found their rhythm in the 24th minute and came close when Stephane Dalmat forced a smart save from goalkeeper Steve Mandanda with a long-range effort.
Ziani eventually broke the deadlock in the 38th minute when his powerful effort flew past Teddy Richert from close range.
The Algerian midfielder almost added to his tally five minutes into the second period, but his drive from the corner of the box was palmed away by Richert.
Eric Gerets' men doubled their advantage 10 minutes later when Mamadou Niang set up Kone who volleyed home from 12 yards out.
The visitors launched a fightback as Erdinc fired home from an offside position that went unnoticed by the referee who allowed the goal to stand.
Buoyed by their good fortune, Les Lionceaux laid siege to the Marseille goal with Mandanda first denying Erdinc from close range in the 84th minute before preventing Jacques Faty from equalising five minutes later.
The young keeper then produced a sensational save in stoppage time, when he managed to get his fingertips to a pinpoint Erdinc header to send his team to the top of the league.
