A double from Mali international Modibo Maiga and a late Cedric Bakambu goal handed Sochaux a 3-0 win which scuppered Toulouse's bid for provisional top stop in Ligue 1 on Saturday.
It was just the second defeat of the season for Toulouse who could have been overnight leaders as they sit equal on 17 points with Paris Saint Germain and Lyon who go head-to-head in a top of the table clash at the Parc des Princes on Sunday.
But the southwestern outfit were trailing after just nine minutes when Maiga opened for Sochaux after picking up a cross from midfielder Loic Poujol.
And the Mali forward formed a deadly tandem with France international playmaker Marvin Martin who set up two decisive passes in the frantic final minutes of play.
A Martin cross resulted in a Maiga header two minutes from time before Bakambu sealed victory two minutes later to bury Sochaux's run of consecutive defeats and 10 goals conceded to Rennes and Auxerre.
Montpellier, meanwhile, have a chance to move second when they travel to Bordeaux later Saturday.
Lorient move up to fifth following a 2-0 win at home against Valenciennes thanks to goals from Joel Campbell (22 min) and Yann Jouffre (69).
Caen ended a spiral of two successive defeats being held 1-1 by visiting Nice but stay seventh, as Auxerre remain ninth after a 1-1 draw against Saint-Etienne.
Tailenders Nancy are still looking for their first win after being held 1-1 at home by newcomers Evian with Dijon and Ajaccio also playing out a 1-1 draw.
Marseille are also in action Sunday, at home to a Brest side which has yet to record a league win as champions Lille face potentially awkward home meeting against Rennes.