PSG, fourth last term before being bought by wealthy Qatari investors and making a host of signings, lost 1-0 to Lorient while Lille drew 1-1 at Nancy and Didier Deschamp's Marseille were held to a 2-2 home draw by Sochaux.
PSG paraded latest recruit Javier Pastore before kick off at a rainy Parc des Princes and they could have done with him on the field rather than in the stands after a limp display.
Striker Kevin Gameiro joined the ambitious outfit from Lorient in June and had one decent chance before watching his old team-mates take the lead after 28 minutes when Julien Quercia tapped in at the far post from a free kick.
Lorient's Kevin Monnet-Paquet earlier missed an open goal from two metres as the modest north west side embarrassed their nouveau-riche opponents, who included other new buys Jeremy Menez, Salvatore Sirigu and Blaise Matuidi.
Lille, surprise double winners last term, have also made several new signings but it was old hand Mathieu Debuchy who opened the scoring at Nancy just after the break following Franck Beria's cross.
Beria turned villain midway through the second half though with an own goal.
Marseille's Lucho Gonzalez, who has spent the close-season waiting for a move away from the club, grabbed a 38th minute opener at the Stade Velodrome before Sochaux hit back twice only for Loic Remy to snatch a draw 16 minutes from time.
"I thought we had done what was needed, above all in the first half in terms of our play and the number of chances," Deschamps told reporters.
Lisandro Lopez, Bafetimbi Gomis and Maxime Gonalons netted for Lyon, who won seven titles in a row between 2002 and 2008 but flattered to deceive under Claude Puel last season and face a fight this term with rivals spending when they have not.
Even promoted side Evian have splashed out by bringing in France striker Sidney Govou and they were sparkling in the first 20 minutes at Stade Brest in their first ever top-flight game before surrendering a two-goal lead to draw 2-2.