PSG were ousted from the top of Ligue 1 thanks to a 1-0 loss to title rivals Lille on a Saturday afternoon further marred by Neymar's sending off.
It is their first loss to Les Dogues at Parc des Princes since 27th April 1996 - 24 matches ago.
Lille made the breakthrough in the 20th minute against the run of play when Jonathan Ikone made a great run down the right to meet Renato Sanches’ pass before cutting it back to the unmarked Jonathan David to fire home.
Inside Europe – PSG favourites but Sampaoli’s team can spring a shock, and Payet will be the key
- Ronaldo strikes late to salvage derby draw for Juventus
- Opinion: Tuchel has finally met Chelsea's wild side, his next moves will be crucial
- Bellingham will have better England career than Dortmund teammate Sancho
It was their only shot of the first half, yet they somehow always seemed more likely to score than their Parisian counterparts who were dominant yet panicky on the ball.
Neymar went closest for them with an acrobatic volley within the first ten minutes and a diving header wide in the second half, but it was a quiet afternoon for fellow PSG star Kylian Mbappe after having an early strike saved by Mike Maignan, who earned a 17th Ligue 1 clean sheet of the season.
Les Parisiens eventually let their frustrations get the better of them, picking up four yellow cards along the way before reaching boiling point when Neymar was sent off for pushing over Tiago Djalo in injury time due to his belief that he was clipped by the young Portuguese defender.
Bizarrely, Djalo was also sent off after the altercation, picking up a second yellow.
Lille face off against ninth-place Metz next Friday, while PSG are away to Strasbourg next Saturday in between the two legs of their Champions League quarter-final against Bayern Munich.
TALKING POINT - A vital win
Much will be of course be made of PSG's woes in front of goal, Neymar seeing red, Mbappe going missing and Pochettino apparently 'bottling it', but steering the focus away from PSG, the importance of this win for Lille cannot be underestimated.
Not only is it important in a historical context, considering their lack of success away to PSG over many years, and it is obviously big to win against your title rivals. However, the impact it could have is amplified by Lille's difficult run-in because it lessens the pressure to win a game they would not have expected to.
Of their remaining seven matches in Ligue 1, Saint-Etienne (16th) and Nice (11th) are the only two opponents in the second half of the table, while Lyon (4th) and Lens (5th) will both be very tricky away trips.
Meanwhile, a league title and the Champions League football that comes with it could help Lille avert their dire financial situation that otherwise might prevent them from building on this youthful, talented squad.
MAN OF THE MATCH - Benjamin Andre
While Lille's young guns will continue to grab the headlines, it is perhaps ironic that a 30-year-old defensive midfielder with no senior international caps is so pivotal to their success, but Andre was fantastic all game. He protected the defence brilliantly, racking up the most duels won (10), tackles (6), interceptions (5) and blocked shots (3) along with his 4 clearances and 8 ball recoveries. It is also a real testament to his defensive efficacy how in such a fiery match a defensive midfielder - probably the most combative role - in a team playing on the back foot only received a yellow card in the closing stages of the game.
PSG: Navas 7, Kehrer 6, Diallo 6, Marquinhos 6, Kimpembe 6, Paredes 5, Gueye 7, Di Maria 7, Mbappe 5, Neymar 5, Kean 5...Subs: Draxler 6, Dagba 6, Bakker 6, Rafinha 6
Lille: Maignan 8, Reinildo 7, Botman 7, Fonte 7, Djalo 7, Soumare 8, Andre 8, Bamba 7, Sanches 7, David 7, Ikone 7...Subs: Weah 6, Yilmaz 5, Bradaric N/A
Barcelona line-up Serie A duo as Haaland alternatives - Euro Papers
7' - CLOSE!! Marvellous run from Di Maria to weave through the Lille defence. He then tees up Neymar whose acrobatic volley goes wide.
15' - SAVED!! Maignan makes an outstanding low save to his left to deny a powerful Mbappe shot!
20' - GOAL!!! Out of nowhere! Lille bomb forward down the right and Ikone cuts it back for his strike partner David to fire home and open the scoring!
69' - CLOSE!! Di Maria finds Marquinhos on the right flank and he whips in a dipping cross for Neymar to head wide.
78' - SAVED!! Lille waste a golden opportunity to put the game to bed! Weah squares it to Yilmaz on the counter but his tame effort is kept out by Navas.
90' - RED CARD!! It gets from bad to worse for PSG! Neymar slips over in the corner while battling with Djalo for the ball. He then gets up and pushes Djalo over unnecessarily, which the referee almost immediately sends Neymar off for!
90' - RED CARD!! Well this one's bizarre...Djalo also picks up a second yellow and thus a red card, but there's no clear reason why and he's justifiably livid. Perhaps he did slightly clip Neymar to bring him down initially, but if there was contact it was minimal.
Round-Up: Salzburg beat Wolfsburg as Villarreal survive Young Boys comeback; Sevilla and Lille draw
‘Everything will be smoother’ - Pochettino admits Messi-Mbappe partnership saved PSG