Sochaux left out the highly-rated Sebastien Corchia after his January transfer to their opponents was cancelled, despite the right-back being presented as a Lille player, and the hosts picked up a routine victory.
Divock Origi gave Lille the lead as early as the third minute and Ryan Mendes added a second in second-half stoppage-time to lift his side above Saint-Etienne.
Sochaux, meanwhile, stay second bottom with 15 points and have statistically the worst defence in Ligue 1 after conceding 46 goals.
Dimitri Payet netted twice inside the first 25 minutes to send Marseille well on their way to a straightforward 3-0 win over mid-table Bastia in Saturday's early kick-off.
The France international moved on to seven league goals this season in the process, with only Andre-Pierre Gignac scoring more in a Marseille jersey this tern
Gignac got his 11th league strike of the season in the 55th minute, wrapping up the 3-0 win and keeping Marseille within two points of the UEFA Champions League places.
Reims kept their European hopes alive by coming from behind to beat hosts Guingamp 2-1.
Rachid Alioui grabbed the opening goal for Guingamp just after the hour mark, but the home side's delight was short-lived as Odair Fortes levelled in the 69th minute.
Floyd Ayite grabbed the winner three minutes later, moving Reims up to sixth while Guingamp stay 16th.
Ajaccio improved their chances of avoiding the drop by beating Rennes 3-1 for only their second Ligue 1 victory this term.
Abdoulaye Doucoure's 33rd-minute goal for Philippe Montanier's men may have cancelled out Ricardo Faty's initial opener, but Benjamin Andre and then Johan Cavalli found the net to wrap up Ajaccio's first league win since September 25.
The odds are still against them, however, with nine points separating Ajaccio from Evian in 17th, who drew 1-1 at Montpellier.
Valenciennes moved to within two points of Evian thanks to a 2-1 victory over Nice, with Abdul Waris netter the winner in the 88th minute.
