Paris Saint-Germain's French Cup hangover continued as Ligue 1 rivals Montpellier came from behind with two late goals to win 3-2 at Stade de La Mosson.
The French champions were beaten in a penalty shoot-out by Rennes in Saturday's final, with forward Kylian Mbappe having been shown a red card for a studs-up challenge.
Thomas Tuchel's side looked to have produced the required response on their return to league action, taking the lead following an own goal from Ambroise Oyongo in the 12th minute.
But Montpellier, who needed victory to keep alive their own European qualification hopes, were level in the 21st minute when Presnel Kimpembe scored his second own goal in two games.
Angel Di Maria's clever finish just after the hour had PSG back on course for victory but Andy Delort equalised again with 10 minutes remaining, before substitute Souleymane Camara snatched a dramatic victory in stoppage time.
PSG came into Tuesday's game with a 16-point lead over second-placed Lille and the title already sewn up.
But their late lapse saw them suffer a first defeat to Montpellier since December 2016.