Pierre-Emerick Aubameyang netted twice to take his season's tally to 19, while Mathieu Bodmer and Renaud Cohade were also on target after Adrian Mutu had struck the opener for Ajaccio with the Romanian then adding a late consolation for the Corsican club.

Victory for Christophe Galtier's side saw them climb above Lille into fourth and close to within two points of Lyon for the final Champions League spot, with second-place Marseille a further two points ahead.

Defeat for Ajaccio means they are just two points clear of the relegation zone, having won just once in their last nine outings.

Wednesday's win comes four days after the euphoria of celebrating Saint-Etienne's first trophy in 32 years following Saturday's 1-0 triumph over Rennes in the French League Cup final.

Meanwhile, Troyes secured a vital three points in their uphill fight to remain in the top division with a 2-1 win at slumping Rennes.

Jean-Christophe Bahebeck gave Troyes an early lead before Jeremie Brechet added a second on 27 minutes, while Julien Feret's penalty on the half hour provided nothing more than a consolation for Rennes, who saw their winless run extended to nine matches.