Bordeaux's title dreams took another blow on Saturday, while Lille suffered a rare defeat.
Elsewhere, Paris St Germain clambered into second spot in the table, Le Mans were unable to put a stop to their winless run and Valenciennes claimed a useful point in their battle against the drop.
Bordeaux have suffered a wobble of late and missed the chance to move within a point of league leaders Lyon as they were held to a 1-1 draw by Grenoble.
Marouane Chamakh broke the deadlock on 61 minutes, but Bostjan Cesar levelled matters on 79 minutes to leave Laurent Blanc frustrated.
That result means that Paris St Germain are now the closet challengers to Claude Puel's men, after they saw off St Etienne 2-1.
The capital club claimed a fourth consecutive victory, and moved within a point of the summit, courtesy of two first-half goals.
Mamadou Sakho (26) and Jeremy Clement (37) struck either side of Dimitri Payet's 35th minute equaliser to take the spoils.
Lille remain well placed to launch a push for European qualification, but slipped to a 2-0 defeat away at Auxerre.
The hosts scored twice in the space of five first-half minutes through Ireneusz Jelen (30) and Kamel Chafnl (35) to claim the points.
Auxerre did have Thomas Kahlenberg dismissed 13 minutes from time, but the game was already safe by that stage.
Le Mans entered their game with Nice without a win in six and saw that run extended to seven games after they slipped to a demoralising 2-1 defeat.
Thorstein Helstad's 52nd minute strike looked for long periods as though it would be the difference between the two sides, but Emerse Fae struck 12 minutes to bring the scores level.
Tempers then threatened to boil as Loic Remy and Gregory Cerdan both saw red to ensure that both sides would end the game with 10 men.
Then, with time running out, substitute Mahamane Traore made himself a hero by snatching a dramatic late winner.
Rennes helped to keep their feint hopes of securing European football alive with a 1-1 draw at home to Nancy.
The visitors went ahead through a 55th minute effort from Youssouf Hadji, but allowed Jimmy Briand to peg them back four minutes from the end.
Caen continue to find victories hard to come by and suffered further misery this weekend as they were held 1-1 by Lorient.
Steve Savidan had them in front after 33 minutes, but Rafik Saifi restored parity less than a minute after the interval.
Valenciennes remain in trouble towards the foot of the table, but they were able to take something from their clash with Nantes.
Rafael Schmitz saw his 13th minute opener cancelled out by Ivan Klasnic just after the hour mark as proceedings ended all square at Stade Nungesser.