Lille title blow with second successive defeat
Saint-Etienne's players celebrate after scoring a goal during a French L1 football match against Lille on January 17, 2014 at the Geoffroy-Guichard stadium in Saint-Etienne, central-eastern France - by Philippe Merle
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.
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.