Amine Gouiri came off the bench to smash home the only goal on Friday as Marseille consolidated their grip on third in Ligue 1 with a 1-0 home victory over relegation-haunted Auxerre.
While Paris Saint-Germain and Lens have opened up a gap at the top, the five teams below them, chasing the last automatic Champions League berth, started the weekend separated by six points.
The victory pulled Marseille three points clear of fourth-paced Lyon, who visit Le Havre on Sunday.
Marseille failed to create a single chance in a lacklustre first half at a subdued Velodrome where the fans at both ends were staging a 45-minute chanting strike. The crowd did find their voices to boo their team off at halftime.
Ligue 1 top scorer Mason Greenwood and Pierre Emile Hojbjerg went close early in the second half.
After 61 minutes, coach Habib Beye replaced centre back CJ Egan Riley with striker Gouiri and the move paid off.
After 79 minutes, the Algeria striker pounced on a poor clearance to power home a match-winning volley.
Marseille survived an 87th minute scare when Auxerre's Bryan Okoh put the ball in the net but replays showed he had done so with his arm.
Auxerre remained in 16th, the relegation playoff spot, five points behind Nice in the first place that ensures safety and two ahead of Nantes in a position that guarantees the drop.
"Marseille did not have much to offer, but we could not capitalise on their weaknesses," said Auxerre coach Christophe Pelissier.
"We can frustrate them, but we cannot punish them."