Paris St Germain suffered a surprise 1-0 defeat to Nancy at the Parc des Princes.
The winning goal came four minutes into the second half, defender Jean Calve's shot beating PSG keeper Salvatore Sirigu.
Despite the loss PSG remain top of Ligue 1 on goal difference. But the points were valuable for struggling Nancy, who moved out of the relegation zone.
The first real chance fell to the visitors when Reynald Lemaitre's shot after six minutes was punched clear by Sirigu.
PSG's best chance of the first half came after 27 minutes when Javier Pastore's volley was blocked by Nancy keeper Guy N'dy Assembe.
Nancy got off to the best possible start in the second half when just four minutes in Calve's shot from the right side of the box flew into the top left corner of Sirigu's goal.
PSG then began to control the match and had the majority of the possession. But they could not beat the excellent N'dy Assembe.
After 62 minutes Christophe Jallet's volley was blocked by the keeper, seven minutes later Mevlut Erding's header was cleared off the line and in the 78th minute Kevin Gameiro hit the crossbar.
With eight minutes remaining N'dy Assembe produced a brilliant double save to deny first Nene and then Mathieu Bodmer.
But the visitors held on and PSG suffered only their second defeat of the season.
