Lille suffered a second successive defeat and squandered vital ground in the French title race when St Etienne grabbed a 2-0 Ligue 1 victory on Friday.
The result left Lille, who ended the game with 10 men after a red card for midfielder Florent Balmont, in third place in the table, seven points behind leaders Paris Saint-Germain and having played a game more.
St Etienne remain fourth, three points behind Lille, thanks to a timely win which followed a midweek French Cup exit at the hands of fourth division Cannes.
Lille had lost 2-1 to Reims last weekend and fell behind after 55 minutes on Friday when Brazilian striker Brandao headed in at the far post from a cross by Algerian defender Faouzi Ghoulam.
Six minutes later it was 2-0 with Franck Tabanou slotting the ball home after Lille keeper Vincent Enyeama had saved from Romain Hamouma.
Lille then had to play the final 30 minutes of the match with 10 men after Balmont was red-carded for aiming a volley of abuse at the referee, who he believed should have ruled out the goal.
"It's a match lost. We played well for an hour but then we went off the boil after conceding the first goal," said Lille coach Rene Girard.
St Etienne coach Christophe Galtier admitted victory was a relief after the Cup exit.
"It was a welcome result because things in midweek were not looking good," said Galtier.
"We could have dropped our heads. I waited impatiently to see how we would react and the players reacted really well."
On Sunday, leaders PSG welcome Nantes to the capital where a win could give them an eight-point lead over Monaco should the second-placed side lose at Toulouse.
Lille suffered a second successive defeat and squandered vital ground in the French title race when St Etienne grabbed a 2-0 Ligue 1 victory on Friday.
The result left Lille, who ended the game with 10 men after a red card for midfielder Florent Balmont, in third place in the table, seven points behind leaders Paris Saint-Germain and having played a game more.
St Etienne remain fourth, three points behind Lille, thanks to a timely win which followed a midweek French Cup exit at the hands of fourth division Cannes.
Lille had lost 2-1 to Reims last weekend and fell behind after 55 minutes on Friday when Brazilian striker Brandao headed in at the far post from a cross by Algerian defender Faouzi Ghoulam.
Six minutes later it was 2-0 with Franck Tabanou slotting the ball home after Lille keeper Vincent Enyeama had saved from Romain Hamouma.
Lille then had to play the final 30 minutes of the match with 10 men after Balmont was red-carded for aiming a volley of abuse at the referee, who he believed should have ruled out the goal.
“It’s a match lost. We played well for an hour but then we went off the boil after conceding the first goal,” said Lille coach Rene Girard.
St Etienne coach Christophe Galtier admitted victory was a relief after the Cup exit.
“It was a welcome result because things in midweek were not looking good,” said Galtier.
“We could have dropped our heads. I waited impatiently to see how we would react and the players reacted really well.”
On Sunday, leaders PSG welcome Nantes to the capital where a win could give them an eight-point lead over Monaco should the second-placed side lose at Toulouse.
