Julian Draxler scored his second goal in as many games since moving to Paris Saint-Germain in a 1-0 victory at Rennes on Saturday.
PSG started in determined fashion and Edinson Cavani should have scored after just 40 seconds.
Having missed four chances in midweek when PSG beat Metz 2-0 to reach the Coupe de la Ligue semifinals, Cavani fluffed his chance by poking wide of goal after being put clean through.
PSG dominated the first half, with Rennes frequently losing the ball.
Draxler cut inside from the left after running onto Marco Verratti's pass but shot straight at goalkeeper Benoit Costil, who also saved from midfielder Blaise Matuidi.
Verratti was enraged when he was not given a penalty after running onto Draxler's excellent pass and rounding Costil, who appeared to take him down. But referee Benoit Bastien instead gave Verratti a yellow card.
The breakthrough came in the 40th mintue as Draxler ran onto an astute pass from Verratti without breaking stride and curled in a delightful shot from the left of the penalty area into the bottom right corner.
Draxler, who joined from Wolfsburg earlier this month in a deal reportedly worth up to €47 million, had scored an equally good goal on his debut in a 7-0 rout of Bastia in the Coupe de France last weekend.
Verratti was still arguing with the referee as the players prepared to start the second half.
Bastien also showed PSG's Thiago Motta a yellow card in the 62nd minute, although he appeared to fall down as he rounded Costil.
Rennes rarely threatened but forward Wesley Said drew a save from goalkeeper Kevin Trapp midway through the second half.
PSG moved level on points with Monaco, who are in second place on goal difference and play on Sunday, as do leaders Nice.