Lille missed the chance to go second in Ligue 1 as they slumped to a 2-1 home defeat to Reims.
Monaco's 1-1 draw with Montpellier on Friday night had left the door open but Lille failed to push through it as Reims took control with two goals in four minutes from Odair Fortes and Grzegorz Krychowiak late in the second half.
An Anthony Weber own goal with two minutes left set up a nervy finish but Reims hung on to maintain their impressive away form, which has seen them lose only once in their last nine on the road.
Lille came into the game in good form themselves, having lost only once in the last 14 matches, and both sides showed attacking intent inside the first 10 minutes.
Salomon Kalou stung the palms of Kossi Agassa before Nicolas De Preville teed up Floyd Ayite at the other end but the Togo international blasted well wide from the edge of the area.
Kalou continued to cause problems and, after Djibril Sidibe's centre eventually fell to him at the penalty spot, the former Chelsea man forced a decent save from Agassa.
Lille continued to huff and puff as Reims remained resolute but Rene Girard's men went close twice just before the interval.
Firstly, Kalou once again found himself in a great position just six yards out after Simon Kjaer headed a Florent Balmont free-kick into his path but Agassa bravely came off his line to smother at the Ivorian's feet.
Then, Lille's number eight went even closer to getting reward for his first-half efforts but, after lobbing Agassa, Weber prevented Kalou the opener when he hacked off his own goal-line.
Lille continued to frustrate in front of goal after the restart and they were almost caught out when Reims hit on the counter but, after breaking free on the right, De Preville dragged a shot wide of the left post as Marko Basa closed him down.
The hosts went agonisingly close again with little over 20 minutes to play but Agassa did magnificently well to turn away Sidibe's shot which seemed destined for the top left corner.
Shortly after though the Stade Pierre-Mauroy was stunned into silence when the visitors found the back of the net twice in quick succession, the first coming in bizarre fashion.
Following some Reims pressure the ball fell to Lille defender Sidibe but his hacked clearance smacked Fortes square in the face before catapulting beyond Vincent Enyeama and into the net.
Then, just three minutes later, Hubert Fournier's side doubled their lead when De Preville flicked on an Ayite corner at the near post and Krychowiak headed home.
Lille managed to reply with just two minutes remaining when Weber put through his own net following a long ball from Kjaer but it was a case of too little too late for Ligue 1's third-placed team.