Match ends, Rennes 1, Paris Saint Germain 3.
Former Stoke City forward Eric Maxim Choupo-Moting scored his first Paris St-Germain goal as the French champions won at Rennes.
PSG were beaten 3-2 by Liverpool in the Champions League in midweek.
Rennes were the last team to beat PSG in Ligue 1, in May, and another upset looked on the cards when Adrien Rabiot deflected into his own net.
Angel di Maria equalised before Thomas Meunier made it 2-1 from Neymar's pass, with Choupo-Moting getting the third.
The Cameroon international, 29, played in 30 Premier League games as Stoke were relegated from the Premier League last season.
He signed a two-year deal with PSG in August after his Stoke deal was cancelled by mutual consent.
Choupo-Moting's goal from inside the penalty area came after a pass by Meunier.
It was only his second appearance for his new club, after he came on as a substitute against Liverpool.
Meanwhile, 40-year-old PSG keeper Gianluigi Buffon produced a superb 74th-minute save to deny Ramy Bensebaini an equaliser when the score was 2-1.
Thomas Tuchel's PSG are five points clear at the top of the table after just six games.
Rennes, who sent on former Newcastle and PSG winger Hatem Ben Arfa as a substitute, have seven points from six games.
Match ends, Rennes 1, Paris Saint Germain 3.
Second Half ends, Rennes 1, Paris Saint Germain 3.
Attempt missed. Hamari Traoré (Rennes) right footed shot from long range on the right is high and wide to the right. Assisted by Clément Grenier.
Attempt blocked. Ángel Di María (Paris Saint Germain) left footed shot from outside the box is blocked. Assisted by Juan Bernat.
Attempt missed. Edinson Cavani (Paris Saint Germain) right footed shot from outside the box misses to the left following a set piece situation.
Substitution, Paris Saint Germain. Christopher Nkunku replaces Neymar.
Hamari Traoré (Rennes) is shown the yellow card for a bad foul.
Edinson Cavani (Paris Saint Germain) wins a free kick in the attacking half.
Foul by Hamari Traoré (Rennes).
Edinson Cavani (Paris Saint Germain) wins a free kick in the attacking half.
Foul by Hamari Traoré (Rennes).
Substitution, Paris Saint Germain. Thilo Kehrer replaces Thomas Meunier.
Attempt saved. Jordan Siebatcheu (Rennes) header from the right side of the six yard box is saved in the top right corner. Assisted by Clément Grenier with a cross.
Corner, Rennes. Conceded by Marquinhos.
Attempt blocked. Hatem Ben Arfa (Rennes) right footed shot from the right side of the box is blocked. Assisted by Ismaila Sarr.
Attempt missed. Benjamin André (Rennes) right footed shot from outside the box is close, but misses to the right.
Goal! Rennes 1, Paris Saint Germain 3. Eric Maxim Choupo-Moting (Paris Saint Germain) right footed shot from the centre of the box to the centre of the goal. Assisted by Thomas Meunier.
Neymar (Paris Saint Germain) wins a free kick in the defensive half.
Foul by Ismaila Sarr (Rennes).
Substitution, Rennes. Romain Del Castillo replaces M'Baye Niang.
Foul by Marquinhos (Paris Saint Germain).
Ismaila Sarr (Rennes) wins a free kick in the attacking half.
Attempt missed. Ángel Di María (Paris Saint Germain) left footed shot from more than 40 yards on the left wing misses to the right.
Offside, Paris Saint Germain. Neymar tries a through ball, but Eric Maxim Choupo-Moting is caught offside.
Substitution, Paris Saint Germain. Eric Maxim Choupo-Moting replaces Marco Verratti.
Adrien Rabiot (Paris Saint Germain) is shown the yellow card.
Hand ball by Adrien Rabiot (Paris Saint Germain).
Substitution, Rennes. Jordan Siebatcheu replaces Benjamin Bourigeaud.
Foul by Edinson Cavani (Paris Saint Germain).
Hamari Traoré (Rennes) wins a free kick in the defensive half.
Foul by Thomas Meunier (Paris Saint Germain).
M'Baye Niang (Rennes) wins a free kick on the left wing.
Attempt missed. Damien Da Silva (Rennes) right footed shot from the left side of the six yard box is close, but misses to the left following a corner.
Corner, Rennes. Conceded by Gianluigi Buffon.
Attempt saved. Ramy Bensebaini (Rennes) right footed shot from outside the box is saved in the bottom right corner. Assisted by Benjamin André.
Foul by Juan Bernat (Paris Saint Germain).
Ismaila Sarr (Rennes) wins a free kick on the right wing.
Corner, Rennes. Conceded by Thomas Meunier.
Attempt missed. Hatem Ben Arfa (Rennes) left footed shot from outside the box is high and wide to the left. Assisted by Benjamin André.
Offside, Paris Saint Germain. Juan Bernat tries a through ball, but Edinson Cavani is caught offside.