Monaco put on a show-stopping 5-0 performance over Bastia, which temporarily moves them to the top of the Ligue 1 table.
Montpellier shocked PSG, scoring on either side of the half to claim a 3-0 win over the reigning Ligue 1 champions.
Paris Saint-Germain CEO and chairman Nasser Al-Khelaifi says the French champions "lost the match before it had kicked off" after the 3-0 defeat.
Paris Saint-Germain lost by three goals in Ligue 1 for the first time in over five years.
The Ligue 1 game between Metz and Lyon at Stade Saint-Symphorien was abandoned after firecrackers exploded in the first half.
Majeed Waris salvaged Lorient a point but they remain without an away win in Ligue 1 this season after a 2-2 draw at Angers.