Lille beat Sochaux 1-0 on Wednesday to all but secure its first French league title since 1954.
Lille wasted several chances before winger Gervinho finally broke the stalemate in the 53rd minute after running onto a pass from striker Moussa Sow and scoring his 15th league goal of the season past goalkeeper Teddy Richert.
With only two matches remaining, Lille leads second-place Marseille by six points and has a much better goal difference.
Rudi Garcia's team needs only to draw Saturday's match at Paris Saint-Germain to guarantee the title.
''It's a great night and we will see if it's enough, it would be just huge,'' Garcia said. ''Marseille has no room for error left.''
Lille is also on track for a domestic double after winning the French Cup last weekend. It previously won the double in the 1945-46 season.
''I am proud of my players, putting in a performance like that four days after the Cup final. I can only take my hat off to them,'' Garcia said. ''We deserved to win. We played well, we put our hearts into it, we were very smart and showed maturity, especially the way we closed them down late on.''
Also on Wednesday, PSG's hopes of finishing third and securing a place in the Champions League qualifying round took a knock after it lost 1-0 at Bordeaux.
After Cheick Diabate scored a sixth-minute penalty for Bordeaux, PSG dominated the rest of the match but it was kept at bay by an inspired performance from goalkeeper Cedric Carrasso.
''It's really hard to take, once again we haven't taken our chances,'' PSG playmaker Nene said. ''We will keep going until the end. We had chances, but unfortunately we conceded a goal early on.''
PSG trails third-place Lyon, which hosts Caen on Saturday, by two points.
''Of course we want to do it. But there's a huge gap between wanting to do it and what we're showing out on the field,'' a frustrated PSG coach Antoine Kombouare said. ''I am very disappointed with the way we started the game because we should have caused them problems, rather than conceding early on. It's the worst possible start we could have had, as it enabled them to gain confidence.''
Lille's fans started to celebrate and the players ran onto the field at the final whistle, just days after Lille won the French Cup to secure its first trophy since winning the French Cup in 1955.
''It's not over yet and we still need a point. Even though it was a great win for us after the French Cup final and the victory could have been even bigger,'' Lille goalkeeper Mickael Landreau said. ''It's really good to have followed up with another win.''
With barely one minute played, Gervinho charged into the penalty area and appeared to be unfairly challenged by defender Damien Perquis, but Lille's penalty claims were waived away.
Gervinho looked in good form early on, hitting the post from Eden Hazard's cross, but then somehow spooning his shot over the crossbar after running onto another Hazard pass and dribbling round Richert in the 19th.
Gervinho teed up Sow in the 40th, and the Senegal striker hit a powerful curling shot that went past the post.
Tempers flared when Hazard was hacked down by Sochaux's Brown Ideye close to the interval, but the Belgium playmaker got back up shortly after theatrically rolling on the ground.
Lille's wastefulness in front of goal finally ended when Sow released Gervinho down the right, and the Ivory Coast winger's shot bounced in off the left post with Richert beaten.
Gervinho should have scored again in stoppage time but blazed over from close range after Richert had saved Tulio De Melo's shot.
Bordeaux took the lead after PSG midfielder Jeremy Clement clumsily tripped left back Benoit Tremoulinas as he cut inside the penalty area.
PSG goalkeeper Gregory Coupet had saved a penalty in Saturday's French Cup final, but this time went the wrong way as Diabate placed his shot into the bottom left corner.
