Monaco's 1-0 win at Rennes on Saturday means Paris Saint-Germain will have to wait a little longer before securing a second straight French Ligue 1 title.
A Monaco defeat in Brittany would have left PSG in a position to secure the championship on Sunday with a win away to Lyon, where they won the title last year, but a solitary strike by Emmanuel Riviere early in the second half gave the principality club the points. Monaco are now ten points adrift of PSG with five matches remaining, although they are more interested in keeping Lille in third at arm's length.
Lille won 1-0 at home to local rivals Valenciennes earlier thanks to a second-half Divock Origi goal, a result that put them eight points clear of fourth-placed Saint-Etienne, who go to Reims on Sunday. Only the top two teams go straight into next season's UEFA Champions League group stage, with the third-placed side having to go through two qualifying rounds to get there and fourth having to settle for the UEFA Europa League.
Monaco coach Claudio Ranieri dropped skipper Eric Abidal for the match at the Stade de la Route de Lorient, while goalkeeper Danijel Subasic missed a league game for the first time this season. The Croatian was replaced in the starting line-up by Argentinian international Sergio Romero, who kept a clean sheet on his Ligue 1 debut.
Only a great save by Benoit Costil at the other end prevented Layvin Kurzawa from giving Monaco the lead in the first half, but the game's only goal arrived ten minutes into the second half, Jeremy Toulalan setting up Riviere to score his tenth league goal of the campaign.
Monaco now turn their attentions to Wednesday's Coupe de France semi-final against Guingamp, and they could end up meeting Rennes again in the final, with Philippe Montanier's side facing Angers in the other semi.
Lille win again to go eight points clear of Saint-Etienne
In Lille, the only goal of the game came for the hosts 20 minutes from time when Salomon Kalou set up Belgian forward Origi, whose shot was deflected into the net off Valenciennes defender Carl Medjani.
The visitors were furious at not being awarded a foul when Simon Kjaer caught Tongo Hamed Doumbia at the other end in the build-up, and they remain eight points adrift of safety with time running out to avoid relegation.
After what was their ninth 1-0 win this season, Lille coach Rene Girard insisted catching big-spending Monaco is not in his thoughts.
"It is not our objective but if they slip up we will be there," Girard said, whose team have a difficult run of fixtures to finish the season, including a trip to Marseille and a home meeting with PSG. "The important thing is to worry about ourselves and to keep going. The end of the season will be tough, but it was good to win tonight to keep us in the running."
Elsewhere, Ajaccio came from behind to draw 1-1 against Bordeaux, with Mehdi Mostefa's late equaliser earning them a draw that postpones their inevitable relegation back to the second tier. However, they will be down if Guingamp claim a point at Nantes on Sunday.
Sochaux kept their survival hopes alive with a 2-0 win against Toulouse, but Evian stay well clear of the drop zone after a 2-1 win against Bastia, while Vincent Aboubakar scored in injury time to give Lorient a 2-1 win at Nice.