Defending champions Lille broke a run of five straight draws with a 2-0 victory over Rennes on Sunday, but Marseille's domestic woes continued in a 1-1 draw at home to Brest.
Lille were held 1-1 at Trabzonspor in the Champions League in mid-week but they quickly took command of the game against Rennes and went ahead in the seventh minute when Moussa Sow rammed home his third goal of the season.
Florent Balmont then flicked in an Eden Hazard free-kick in the 32nd minute to secure a victory that sent Rudi Garcia's side up to fifth in the table.
Despite a fine 3-0 defeat of Borussia Dortmund in the Champions League on Wednesday, Marseille have just one win to their name in nine Ligue 1 matches and sit 13th after their stalemate with Brest.
Romain Poyet gave the visitors the lead in the fifth minute with a tame shot that Steve Mandanda somehow allowed to creep underneath him.
Andre Ayew equalised in the 19th minute, tapping home Loic Remy's centre, but OM failed to put the visitors under real pressure in a dreary second period.
Co-leaders Paris Saint-Germain and Lyon will each be seeking to prove their title credentials when they face off at Parc des Princes in Sunday's late game.
The hotly anticipated showdown pits PSG's expensively assembled side against Remi Garde's rejuvenated OL line-up and the build-up to the game has dominated the French sporting agenda in recent days.