Lille snatched a 2-2 draw at relegation-threatened Evian in the French league on Sunday to boost its Champions League hopes.
Lille looked to be heading for a surprise defeat before substitute Ryan Mendes' stoppage-time leveler.
"We got a point, we didn't lose, that's the main thing," Lille coach Rene Girard said. "It's never easy to come here. I'm happy with the bravery of my boys. I knew it would be a battle of a match, and that's what it was.
"It was hard to impose our game but I think we deserved to level at the end of the game. Credit to us that we believed right up until the end."
Lille remained third, three points above Saint-Etienne which also needed a stoppage-time equalizer to rescue a 1-1 draw at home to Marseille.
Lyon is level on points with fifth-placed Marseille after a comfortable 3-1 win at home to bottom club Ajaccio.
Evian, which is three points off the bottom three, took the lead in the 15th minute when Modou Sougou floated in a superb cross from the right and Kevin Berigaud headed in at the far post.
Teenage forward Divock Origi leveled eight minutes later with an impressive solo effort but Cedric Mongongu scored from the penalty spot shortly after the hour mark when Pape Souare handled in the area.
Mendes snatched a point for Lille when his cross went in off the far post.
Saint-Etienne had won its past five league games without conceding a goal but Marseille seemed to be heading for victory and fourth spot after Nicolas Nkoulou was left unmarked at the far post to volley home Dimitri Payet's free kick in the 64th minute.
But Brandao headed in off the post in added time to earn Saint-Etienne a point.
Lyon is five points behind Lille after its earlier victory.
Gueida Fofana curled in a superb pass from Alexandre Lacazette to give Lyon the lead two minutes from halftime, after Ajaccio had hit the post early on.
Substitute Jimmy Briand extended Lyon's advantage in the 68th when he was left unmarked to head Henri Bedimo's cross into an empty net.
Dennis Oliech pulled one back for Ajaccio 10 minutes from time but Bafetimbi Gomis sealed the result with a powerful effort in stoppage time.
Ajaccio, which hasn't won any of its past 24 away matches, is 10 points off safety.