Paris St-Germain missed out on the chance to wrap up Ligue 1 for the second weekend in a row as they were thrashed by second-placed Lille.
Thomas Meunier’s own goal put Lille ahead but Juan Bernat levelled – before being sent off for a professional foul on Nicolas Pepe after 36 minutes.
Pepe finished off a one-on-one and Jonathan Bamba smashed in at the near post to put Lille in control.
Headers from defenders Gabriel and Jose Fonte turned it into a rout.
This was the first time PSG had conceded five in a league game since 2 December 2000, when they lost 5-1 at Sedan in what was then called Division 1.
It was a night to forget all round for PSG, who had two Mbappe goals ruled out for offside and lost captain Thiago Silva and Meunier to injury in the first half.
PSG had been expected to win the league last weekend, but drew 2-2 with Strasbourg in a game that will be remembered for Eric Maxim Choupo-Moting missing an open goal.
Thomas Tuchel’s Double-chasing side have a third chance to seal the title on Wednesday, needing a win at Nantes to seal a fifth French championship in the past six seasons.