Former Romanian international Adrian Mutu scored twice in the second half as unfancied Corsican side Ajaccio upset seven-time champions Lyon 3-1 in the shock of the weekend in France on Sunday.
The result means Remi Garde's remain three points behind leaders Paris Saint-Germain, who returned to the summit following their 4-0 dismantling of Toulouse on Friday that was fuelled by Swedish striker Zlatan Ibrahimovic's league leading 20th goal of the season.
France under-21 striker Alexandre Lacazette volleyed Lyon in front on 53 minutes after an uneventful first half but they could only protect their advantage for four minutes before their relegation-threatened rivals levelled the tie at their Francois Coty stadium.
Moroccan international Chakhir Belghazouani pounced on a loose ball in the box and fired the ball past an unprepared Remy Vercoute in the Lyon goal for the equaliser. It was then left to Mutu, the former Chelsea, Juventus and Fiorentina star who has endured a troubled career before surprisingly signing with Ajaccio in the off-season, to roll back the years with two late strikes.
A confident header on 65 minutes from a Johan Cavelli cross put the home side in front and then, with Lyon pushing forward in search of an equaliser, they conceded a penalty that the 34-year-old tucked away to put the result beyond doubt with his seventh goal of the season.
Defending champions Montpellier, who have climbed to ninth after flirting with the relegation zone earlier in the season, are in action later Sunday, while third-placed Marseille must win at the Velodrome, where they have to beat basement dwellers Nancy to move level with Lyon and close to within three points of PSG.