Goals from Roy Contout and Delvin Ndinga lifted Auxerre out of the Ligue 1 drop zone with two games to play but left free-falling hosts Dijon staring relegation in the face.
Auxerre started bottom of the table but buoyed by Sunday's 4-0 win over Brest, and victory saw them jump four places while Dijon slipped to second-bottom on the back of their fifth straight loss.
Dijon had started brightly in a game re-arranged from Wednesday due to bad weather, with Benjamin Corgnet firing a powerful right-foot shot from 25 yards which was well saved by Auxerre goalkeeper Olivier Sorin.
The visitors grabbed the lead in the 28th minute when Alain Traore cut in from the left between two defenders and crossed for Contout to firmly head the opener past Baptiste Reynet.
Reynet prevented Auxerre going further ahead when he saved from Olivier Kapo two minutes later, but Dijon missed a glorious chance to equalise on 42 minutes when Brice Jovial headed wide with the goal at his mercy.
Dijon continued to push at the start of the second half with Eric Bautheac firing just wide, then the same player skimming the bar with a rising effort after a poor clearance by Stephane Grichting.
The hosts hit the bar again on 74 minutes from Jovial's 25-yard shot, but Dijon were made to pay five minutes from time when Ndinga burst out of midfield and fired a superb second from long range.