Lorient shocked Paris Saint-Germain (PSG) with a 3-1 victory at the Parc des Princes after the Ligue 1 leaders were reduced to 10 men.
PSG were reduced when Achraf Hakimi was sent off early in the first half and they have now lost nine games in all competitions in this year.
They remain on 75 points from 33 games and they could see their Ligue 1 lead cut to five points if Olympique Marseille beat Auxerre later on Sunday.
Lorient moved up to 10th.
Lorient took the lead in the 15th minute with some neat interplay on the right flank which stretched the PSG defence.
This allowed Romain Faivre to put the ball into the box where an unmarked Enzo Le Fee fired home.
PSG were down a man five minutes later when Hakimi received his second yellow card after a late challenge on Darline Yongwa.
Kylian Mbappe then equalised in bizarre circumstances following an error from goalkeeper Yvon Mvogo.
The Swiss goalkeeper recovered the ball and attempted to restart play by rolling it forward.
But Mbappe —- who was walking back right beside him —- took the ball and pushed into an empty net.
With the one man advantage, Lorient took the game to PSG with Le Fee and Faivre pulling the strings.
The second goal came when Faivre danced into the box and his deflected cross from the byline fell to Yongwa, who made it 2-1.
Amid jeers from the home fans, PSG huffed and puffed in search of an equaliser.
Sergio Ramos headed over from a Lionel Messi corner-kick, while Mvogo also saved a Danilo Pereira header with his face.
Bamba Dieng had a late goal ruled out for offside but he scored Lorient’s third a minute later to seal all three points.
That was when he went one-on-one with goalkeeper Gianluigi Donnarumma, who saved the first effort before Dieng bundled it home.
PSG’s Galtier slams “very stupid” Hakimi red card in loss to Lorient
Achraf Hakimi’s red card in the loss to Lorient by Paris Saint-Germain (PSG) was “very stupid”, club coach Christophe Galtier said, asking his side to be more ambitious.
The Ligue 1 champions slipped to a 3-1 defeat after they lost the defender inside the first 20 minutes to a second yellow card offence.
The loss leaves PSG still with an eight-point cushion at the summit, although it would be slashed to five if rivals Marseille were to win against Auxerre later on Sunday.
Reflecting on Hakimi’s red card, which came after poor challenges on Romain Faivre and Darlin Yongwa, Galtier professed his frustration with both the player and his side’s wider performance.
“[There is] no reason for Achraf to be tense and nervous,” he said. “The second card is very stupid. [There was] no sign this week that he would be tense.
“It’s a big disappointment, and we have to react quickly because we don’t know how many points we’re going to have. Our second half of the season [has been] very, very average.
“There needs to be a collective but also an individual awareness. Too many players are looking inward. We have to look ahead.
“The Troyes match is coming up. We’ve been first since the start of the championship, but we have to finish with victories. We have the ambition to do more.”