Sloan Privat denied Lyon the chance to go top of the Ligue 1 table after his second-half goal earned Sochaux a valuable point from a 1-1 draw.
With Marseille being held at the death by Nice in today's early game, top spot was there for the taking and Maxime Gonalons' goal halfway through the first half put Les Gones on course for the summit.
But the hosts rallied and Privat's cool finish saw Les Lionceaux match 17th-placed Evian on 11 points in their bid to escape the drop.
Lyon goalkeeper Remy Vercoutre had to look lively in the 20th minute as Ryad Boudebouz stormed into the box but three minutes later the ball found its way into the net at the other end.
Steed Malbranque curled a free-kick into the box from 35 yards, Gonalons stepping forward to slot home his second goal in as many games.
Les Gones could have doubled their lead before the break but Simon Pouplin guessed right when Alexandre Lacazette arrived in his area.
Pouplin blocked Rachid Ghezzal as play resumed and he earned hearty applause in the 54th minute by deflecting Lisandro Lopez's close-range effort behind for a corner.
Sochaux began to grow in confidence, laying siege to Vercoutre's goal, with the Lyon stopper having to deny Abdoul Camara before repelling a Privat header at full stretch.
But he was beaten in the 70th minute, Boudebouz releasing Privat with a long ball from deep and the French Guiana-born striker skipping past Milan Bisevac to rifle the ball home.
Remi Garde knew top spot was still there for the taking, though, and instructed his men to pile forward, but Pouplin would win the duel as Lisandro danced through on goal unchecked.
A solitary point was enough for Lyon to leapfrog St Etienne and Valenciennes into third place, while Sochaux stay 18th.