Moise Kean scored the only goal as Paris Saint-Germain beat Caen 1-0 in their Coupe de France round-of-64 clash at Stade Michel d'Ornano on Wednesday.
The holders – who have won the competition a record 13 times – were poor in the first half and went in at the break having had just one shot on target.
Mauricio Pochettino's side came out for the second period with renewed purpose, though, and broke the deadlock soon after thanks to on-loan Everton striker Kean's 12th goal of the season in all competitions.
Caleb Sery squandered a golden opportunity to equalise late on, but PSG ultimately held firm to extend their unbeaten run against Caen to 18 matches with the minimum of fuss.
The hosts twice went close inside the opening five minutes, Sergio Rico pawing over Aliou Traore's fierce strike from distance and Hugo Vandermersch missing the target with a free header inside the six-yard box.
Julian Draxler headed wide from Neymar's lofted ball over the top in the 42nd minute, but PSG – sorely lacking the pace of Kylian Mbappe in the first half – were unable to find an opener before the interval.
Pochettino's men were a lot sharper after the restart and went ahead after 49 minutes, Kean diverting Neymar's left-wing cross past Sullivan Pean.
Pean superbly denied Kean a second three minutes later, getting a strong hand to the Italian's powerful drive after he had been played in by Leandro Paredes.
PSG handed a debut to highly rated former Barcelona youngster Xavi Simon with 12 minutes remaining, while the Ligue 1 champions were lucky not to concede in the closing stages as Sery inexplicably fired wide from 10 yards.