Dani Alves’ wonderful opener was cancelled out by defender Diego’s brace and Abdul Majeed Waris’ strike as Nantes took control. Metehan Guclu then scored a late consolation.
PSG remain 17 points clear at the top of the table and host Monaco on Sunday.
Boss Thomas Tuchel rejected suggestions the club were in crisis after the 5-1 thrashing against Lille and they were on course for the title when Alves brilliantly opened the scoring in the 19th minute.
The defender collected the ball 30 yards out and unleashed a swerving strike which dipped into the top corner.
But the visitors’ lead was short-lived when Diego levelled just three minutes later.
Poor defending allowed the centre-back to power in a header from captain Valentin Rongier’s corner.
Waris made it 2-1 a minute before half-time when he tapped in at the far post following good work from Kalifa Coulibaly and Samuel Moutoussamy.
Diego then grabbed his second seven minutes after the re-start, fortuitously scrambling in from a corner.
Eric Choupo-Moting hit the post for PSG before Guclu pulled a goal back with a minute left.
*Copy provided by Press Association Sport
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