Lille passed up the opportunity to move into third in Ligue 1 after bottom-side Montpellier grabbed a late equaliser against Bruno Genesio's side on Sunday.
Jonathan David twice gave Lille the lead from the penalty spot in either half but Issiaga Sylla struck in first-half injury time and Arnaud Nordin then found a 93rd-minute leveller for Montpellier as the points were shared in the southern French city.
A draw leaves Lille still in fourth but with 23 points, the number amount as third-placed Marseille with Roberto De Zerbi's side in action later on Sunday against second-placed Monaco.
Montpellier stay rooted to the foot of the table, five points from safety.
Canadian attacker David broke the deadlock in the 44th minute as he sent Benjamin Lecomte the wrong way from 12 yards after Matias Fernandez-Pardo was felled in the box at the end of a rapid Lille counter-attack.
The lead only lasted three minutes with Sylla rising highest to glance home a corner on the stroke of half-time.
David was back to face Lecomte from the spot nine minutes into the second half as the referee decided following a lengthy VAR intervention to award a penalty for a trip on Remy Cabella.
The visitors appeared set to move to 25 points until the third minute of stoppage time.
Lille failed to clear the danger from a cross and after ping-ponging around the box, the ball landed for Nordin who finished gleefully from close range.
Montpellier forward Tanguy Coulibaly was sent off in the 99th minute for firing the ball at Lille coach Genesio after a foul was given against the Frenchman.
In the chaotic aftermath of the incident, Lille substitute Mitchel Bakker was also given his marching orders.
Later, Marseille host Monaco with three points separating the pretenders to Paris Saint-Germain's title, while Angers visit Le Havre and Lyon welcome rivals Nice.