Hatem Ben Arfa scored his first Nice hat-trick as the south coast side leapfrogged Rennes into fourth with a win against their rivals for a European place.
Nice took charge early on and could easily have been one up inside 25 minutes when Romain Danze turned Ricardo Pereira's cross beyond his own keeper but the crossbar came to the Rennes defender's aid.
The hosts had a goal ruled out at the half hour mark after Benoit Costil was fouled before Nempalys Mendy headed home but moments later the visiting keeper was beaten again but this time it stood.
Sylvain Armand brought down Jean-Michel Seri inside the area and, from the resulting spot-kick, Ben Arfa beat the diving Costil to hand Nice a deserved lead.
And Ben Arfa grabbed his second of the game to hand Claude Puel's side a 2-0 lead at the break, firing in off the left post after latching on to Vincent Koziello's neat through ball.
Ben Arfa had not finished there and waisted no time in sealing his hat-trick after the restart in stunning fashion, firing across Costil after being allowed to travel with the ball.
Ben Arfa was replaced to a standing ovation with less than 20 minutes left to play and the hosts saw out the remainder of the game to put to bed last week's 4-1 defeat to PSG.
ends