Marseille and Lyon both came from behind to breathe new life into their title challenges on Saturday, with OM beating Sochaux 2-1 and OL overpowering derby rivals Saint-Etienne 4-1.
Andre-Pierre Gignac was the match-winner for Marseille at Sochaux, as the defending champions secured a victory that took them up to second place in the Ligue 1 table.
Brown Ideye put Sochaux ahead in the 43rd minute but Gignac equalised two minutes later, collecting a pass from Lucho Gonzalez and bending a low strike into the bottom-right corner from the edge of the penalty area.
Gignac had scored just one league goal prior to the winter break but his winning goal with 20 minutes to play took his tally to four in his last four league matches.
"The most important thing is that the team wins," said Gignac, whose side were jeered by their own fans during last weekend's 1-0 defeat of rock-bottom Arles-Avignon.
"It's good to score and to help the team win. Tonight it was very important. We had to win and it's job done.
"It's good for the confidence of the team and for me. But we can't stop here, we have to keep working."
PSG were held to a 0-0 draw at home to struggling Lens, who slipped one place to second-bottom in the table despite leaving the capital with a doggedly earned point.
Guillaume Hoarau hit the post for PSG in the first half and Mevlut Erding failed twice from close range in the second period, first being denied by Lens goalkeeper Vedran Runje and then blazing over from Hoarau's knock-down.
"We're obviously disappointed. We had opportunities to win it but we didn't manage to score," said PSG midfielder Clement Chantome.
"We can't allow ourselves to miss so many chances. We don't know how to kill the game."
Lyon moved level on points with PSG, four points shy of Lille, after avenging the 1-0 loss at home to Saint-Etienne in late September that had left them 18th in the table.
Lyon withstood strong pressure from the hosts and managed to turn the game around after two Yoann Gourcuff corners sparked panic in the home defence.
From the first, in the 28th minute, Bafetimbi Gomis lashed in the equaliser against his former club and from the second, five minutes before half-time, Cris's header was inadvertently diverted into his own goal by Mustapha Bayal.
Substitute Jimmy Briand tapped home Lyon's fourth goal in injury time.
Elsewhere, Monaco boosted their fight against the drop by beating Lorient 3-1 to close to within a point of fourth-bottom Auxerre, who lost 3-1 at Nancy.
Source: AFP Global Edition