Defender Achraf Hakimi scored a debut goal as Paris Saint-Germain began its bid to wrestle back the French league title with a 2-1 win at Troyes.
Promoted Troyes stunned PSG by taking the lead in the eighth minute when defender Oualid El Hajjam headed in powerfully from a corner.
After joining from Italian champion Inter Milan for 60 million euros ($70.5 million), Hakimi equalized with a crisp shot past the Troyes goalkeeper after breaking free down the right in the 18th.
Two minutes later, striker Mauro Icardi showed good composure and awareness to control a pass from striker Kylian Mbappe and flick the ball in with the outside of his foot.
Mbappe went close again, but Troyes center forward Renaud Ripart was also lively and twice denied by goalkeeper Keylor Navas.
"It was a very difficult game and we didn't start it well. We need to do much better," PSG coach Mauricio Pochettino said. “We conceded far too many chances for my liking."
Much of the attention before the game was off the field.
PSG is locked in talks to sign Lionel Messi, after his new deal with Barcelona collapsed this week.
"His name is associated with many clubs, there are a lot of rumors," Pochettino said. "We will see what happens in the next few days."
Coach Peter Bosz began his Lyon career with a tame 1-1 home draw against Brest.
The Dutchman was fired by Bundesliga side Bayer Leverkusen last March.
Bosz replaced Rudi Garcia, who led Lyon to fourth last season and missed out on Champions League qualification.
Forward Islam Slimani earned him his first point in French soccer when he canceled out Brest's first-half opener from striker Striker Irvin Cardona.
Brest fought hard to stay up last season and finished 17th.
Cardona gave his side the lead shortly before halftime with a fine strike from 20 meters.
Slimani equalized in the 62nd when he swept the ball home after strike partner Karl Toko Ekambi headed the ball to him.
Lille is at Metz on Sunday.
Monaco drew with Nantes 1-1 in Friday's season-opening game.
