Mario Balotelli scored the winner against his old club as Marseille beat Nice 1-0 at the Stade Velodrome.
Balotelli headed past Walter Benitez in the 61st minute to make it five goals in seven Ligue 1 games for the Italy striker since leaving Nice and joining Marseille in January on a deal until the end of the season.
Rudi Garcia's team, who have won five times in a six-match unbeaten run, are now three points behind third-placed Lyon. Patrick Vieira's Nice are ninth.
The first chance of the contest fell to Marseille's Valere Germain, who was unable to direct his header on target from a Florian Thauvin free-kick in the sixth minute.
Three minutes later Balotelli met a corner with a volley, but his effort was blocked by Christophe Jallet.
Thauvin then had a weak shot gathered by Benitez before the visitors had their first effort of note as Allan Saint-Maximin's drive was parried by Steve Mandanda.
Three minutes later, the ball came to Balotelli in a good position but he opted to head to a team-mate but Christophe Herelle was on hand to make the clearance.
Nice were forced into a change soon after, with Jallet having to come off for Patrick Burner following a challenge with Bouna Sarr, and Marseille then went the closest to opening the scoring as Thauvin cut in from the right and saw his curling shot tipped over the bar by Benitez.
Saint-Maximin fired into the side-netting early in the second half before Balotelli – who ahead of the game had expressed his desire to stay with Marseille beyond the summer – broke the deadlock as he got his head to a Lucas Ocampos cross.
There was no repeat on this occasion of the memorable celebration he had produced after scoring against St Etienne a week earlier, when he grabbed a phone and recorded himself, his teammates and the fans.
However, the striker did have time to sit with Thauvin and celebrate his effort with a game of rock-paper-scissors by the corner flag.
Ocampos saw his shot saved by Benitez in the 72nd minute and Adrien Tameze then looped an effort over the Marseille bar from outside the box.
Substitute Dimitri Payet sent a free-kick goalwards in the closing moments of the game which Benitez collected comfortably.
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