In-form striker Nicolas Pepe scored what proved to be the winner as 10-man Lille claimed a 3-2 win at Nimes on Sunday to consolidate second place in Ligue 1.
Later on Sunday, Lyon won 3-0 at home against struggling Monaco to move into third.
Lyon are three points behind Lille with a match in hand, while Montpellier, who did not play for a second consecutive week, are another two points back but have played two games fewer than Lille.
The French title race is all but over with reigning champions Paris Saint-Germain 10 points clear, but a young Lille side are eyeing a return to the Champions League group stage for the first time since 2012.
“What a match, I’m really proud of my players,” said Lille coach Christophe Galtier. “We must not forget that we played for more than an hour and 20 minutes with 10 men.
“With the added time, it was a very long and hard match physically.”
Portuguese teenager Rafael Leao headed Lille into a fourth-minute lead, but Galtier’s men suffered a setback when former Southampton centre-back Jose Fonte was sent off in the 16th minute.
Jonathan Bamba’s deflected effort doubled the advantage shortly before the interval, though, and Pepe appeared to have made the points safe midway through the second half with his 12th goal of the campaign.
The 10 men finally started to tire late on, but Lille held on for victory despite Nimes goals from Rachid Alioui and Clement Depres.
In the late game, Lyon dominated Thierry Henry’s Monaco from beginning to end. They took the lead in only the sixth minute with a goal by Houssem Aouar, his sixth of the season.
Nabil Fekir added the second in the 34th minute, attacking Kenny Tete’s low cross as Monaco’s Jemerson hesitated.
Monaco managed only one shot all game. They played almost the whole second half with 10 men after Aleksandr Golovin raked his studs down the back of Fekir’s calf in the 47th minute and was sent off.
Ferland Mendy added a deserved third for Lyon just before the hour mark.