Last-gasp Pedretti goal sends Auxerre top
Pedretti netted with a low shot in stoppage time, just after Thorstein Helstad of Le Mans had cancelled out Ireneusz Jelen's first-half opener.
Poland striker Jelen collected a Denis Oliech cross and coolly slotted home in the 25th minute for his 10th league goal of the season.
Auxerre then sat back and were caught off guard in the last minute as Helstad headed in a free kick.
The hosts, though, hit back straight away when former France midfielder Pedretti was perfectly set up in the box by a pass from Oliech.
Elsewhere, Ghana striker Asamoah Gyan netted twice as Stade Rennes rose to seventh with a 4-1 win over Toulouse.
Paris Saint-Germain's miserable season continued, losing for the 12th time in the league with a 1-0 defeat at Nice.
The game was played behind closed doors after the French league took disciplinary action against Nice for their fans' bad behaviour at Monaco earlier this season.