Here is what went down at the Stade Louis II…
Scorers: Golovin 4′, Wissam Ben Yedder 18′, 45+2′; Zäire-Emery 39′.
Monaco showed their worth by snatching a shock two-goal lead in the first 20 minutes.
Aleksandr Golovin broke the deadlock in the opening stages before Wissam Ben Yedder stung the Parisians, latching on to a mistake by El Chadaille Bitshiabu before slotting past Gianluigi Donnarumma from a right angle.
16-year-old Warren Zaïre-Emery pulled one back for the champions just before the break to give some hope as they seemingly headed into the break.
However, Monaco restored their two-goal advantage with almost the last kick of the half, as Ben Yedder was played in behind before stabbing home from a sharp angle to stun the league leaders once again.
PSG pushed to claw back into the game throughout the second half, coming at the Monaco defence in waves but their efforts went unrewarded as the hosts proved to be a tough nut to crack.
The inability to break the home side down saw a twist in the tale at the top of the Ligue 1table.
While PSG remain firmly in first, the loss gives chases Marseille a chance to finish the round within five points of the top if they can beat Clermont-Foot later on Saturday.