Ligue 1 Wrap: Marseille return to second spot
An 11th consecutive home win for Marcelo Bielsa's men was sealed four minutes after the break, when Dimitri Payet was fouled in the box by Cedric Barbosa, allowing France international Andre-Pierre Gignac to duly dispatch the resulting spot-kick.
The hosts could have added a second late on, but Payet's vicious volley was denied by the crossbar.
The result sees Marseille go level on points with Paris Saint-Germain, one behind leaders Lyon.
Elsewhere, Montpellier's hopes of securing a UEFA Champions League spot were handed a setback as they were held to a 0-0 draw at Lorient.
Despite extending their unbeaten run in the league to seven games, Rolland Courbis' men are now 11 points off the top three and face a real fight if they are to seal a place in Europe's premier club competion.
The only other game to end goalless was Nice's trip to bottom-of-the-table Metz, which was played under difficult snowy conditions that saw most of the pitch markings having to be redefined at half-time.
The visitors were reduced to 10 men late on when substitute Neal Maupay was dismissed for a push on Sylvain Marchal, but the hosts could not take advantage on yet another frustrating outing.
A miserable season shows no sign of getting any easier for Metz, whose winless run in the league now stretches to 11 games, leaving them firm favourites to make a swift return to the second tier.
Elsewhere at the bottom, an Aleksandar Pesic goal ensured Toulouse eased their relegation concerns with a 1-0 win at home to Reims, while also halting a winless run of seven games in all competitions.
In the day's other two games, Lille avoided a third successive Ligue 1 defeat with a 1-1 draw at Nantes.
Jonathan Delaplace gave the visitors the lead after 14 minutes, before Oswaldo Vizcarrondo popped up to rescue a point 10 minutes from time.
It also finished a goal apiece in the game between Lens and Bastia, with second-half spot-kicks from Ryad Boudebouz and Ahmed Kantari ensuring a share of the spoils.