Rennes lost their 100 percent record in Ligue 1 on Sunday when visitors Nice came from behind to beat them 2-1 with a stoppage-time goal by Racine Coly.
Nice, bought by British billionaire Jim Ratcliffe's company Ineos this week, levelled with a penalty in the 63rd minute, Wylan Cyprien scoring from the spot for the second game in a row after Youcef Atal was fouled by Hamari Traore.
Patrick Vieira's side then took all three points when Coly turned the ball in at the far post after a corner was headed on.
"It's a team of young players but I work with them every day and I see their concentration, their desire to learn," said Vieira. "They have determination, seriousness, they have been fantastic today."
The result left Paris St Germain, Rennes, Nice and Angers all level on nine points from four games with the Parisians leading on goal difference.