Paris Saint-Germain suffered a late capitulation to record a stunning 3-2 defeat away at relegation-threatened Lorient in Ligue 1.
Mauricio Pochettino's side looked to be in the driving seat heading into the closing stages after two Neymar penalties had given them a 2-1 lead.
But they allowed Lorient to snatch victory at the end and the result means that Lyon are top of the table, with PSG now a point behind.
Lorient 3-2 PSG Player Ratings: Neymar shines but disaster for Kimpembe
PSG were lacklustre in the opening exchanges and a poor piece of defending on the edge of the area from multiple players allowed Laurent Abergel to drift in and lift his superb shot into the top corner for the lead.
But PSG levelled just before the break with Neymar, who was their only positive from an attacking perspective on the day, driving into the area only to be fouled by Houboulang Mendes, and allowing him to step up and convert the spot kick.
And it took another penalty to put them ahead, this time Mauro Icardi the man fouled inside the box and Neymar once again did the business from the spot.
But PSG regressed into their own territory and allowed Lorient to begin to attack in numbers, and the equaliser arrived with 10 minutes to play.
Substitute Yoane Wissa ran a considerable distance at the PSG defence before lashing his shot high into the net for 2-2.
And from a PSG perspective, the unthinkable happened, when the visitors pushed everyone forward to find a late winner and were caught on the counter, with another sub, Terem Moffi, outpacing Presnel Kimpembe to slot past Sergio Rico for a famous win.
The thrilling Ligue 1 title race continues and Lille have the opportunity to overtake both PSG and Lyon to return to the summit with victory against Dijon.
Lorient 3-2 PSG Player Ratings: Neymar shines but disaster for Kimpembe
Assist given by Laurent Abergel.
Goal by Terem Moffi.
Yellow card for Laurent Abergel.
Substitute in, Idrissa Gana Guèye.
Substitute in, Pablo Sarabia.
Substitute out, Leandro Paredes.
Substitute out, Ángel di María.
Goal by Yoane Wissa.
Substitute in, Pierre-Yves Hamel.
Substitute out, Enzo Le Fée.
Yellow card for Leandro Paredes.
Yellow card for Fabien Lemoine.
Substitute in, Yoane Wissa.
Substitute in, Terem Moffi.
Substitute out, Armand Lauriente.
Substitute out, Adrian Grbic.
Substitute in, Jonathan Delaplace.
Substitute out, Houboulang Mendes.
Penalty scored by Neymar Jr.
Substitute in, Trevoh Chalobah.
Substitute out, Thomas Monconduit.
Penalty scored by Neymar Jr.
Goal by Laurent Abergel.
Yellow card for Thomas Monconduit.
Yellow card for Enzo Le Fée.
Yellow card for Danilo Pereira.