Bordeaux got back to winning ways with a thrilling 4-2 victory. Adam Ounas (19'), Diego Rolan (37'), Clément Chantôme (67') and Cheick Diabaté (89') scored to end a run of three consecutive defeats in all competitions for FCGB.
There were chances aplenty at either end at Roazhon Park on Friday night, but Rennes took the spoils when Arnold Bouka Moutou turned the ball past his own goalkeeper (90+1') with the final act of the game.
Paris Saint-Germain's Brazilian left-back Maxwell explained how the dominant champions are happiest when firing on all cylinders, also expressing his admiration for his eventual successor, France international Layvin Kurzawa.
Paris Saint-Germain's winning run of nine Classiques against Olympique de Marseille dominated the stats for Week 25; Rémy Cabella's strike was a milestone for the season, as was the first of Floyd Ayité's for SC Bastia.