Despite playing the final 40 minutes of the match with nine men, Rennes was able to hold off PSG and claim a 2-1 win at the Parc des Princes on Saturday.
The loss is PSG's second straight at home and leaves the club level with Marseille on 23 points at the top of the table, although Marseille now has two games in hand.
Rennes jumped out to an early lead when Romain Alessandrini scored on a fantastic volley, only for the home side to answer back eight minutes later with a goal from Nene.
Rennes goalkeeper Benoit Costil was sent off for bringing down PSG's Jeremy Menez just outside the penalty area, but the visitors snatched the lead back before halftime with 10 men as Julien Feret's free kick made its way past the wall and found the back of the net.
PSG then had a two-man advantage for the final 40 minutes of the match after Jean Makoun picked up his second yellow card for a foul on Nene.
The hosts had chances but Guillaume Hoarau's shot crashed against the crossbar before Javier Pastore's rebound attempt struck the post.
Rennes goalkeeper Cheikh N'Diaye did well to preserve the lead over the final 10 minutes, giving his team its sixth win in seven matches.
Sochaux 1, Ajaccio 0
Ajaccio, France - Sochaux ended a poor run of results on Saturday with a 1-0 victory at Ajaccio courtesy of an own goal from the home side's Samuel Bohours.
Sochaux began the weekend in the bottom three after a run of just one win from its last six matches. But Saturday's result lifts the club two points above the drop zone and level on 14 points with Ajaccio.
The hosts nearly had a great start when Adrian Mutu's header came back off the post inside of 10 minutes, but they fell behind when Sochaux's Roy Contout had his cross turned into the net by Ajaccio's Bohours.
Brest 3, Bastia 0
Brest, France - Bastia was handed its third straight defeat on Saturday at Brest as Larsen Toure netted a goal in each half to carry the home side.
Toure's first goal came just before the break, and Bastia was reduced to 10 men five minutes after halftime when Francois Marque was sent off.
Brest wasted little time in adding to its lead as Eden Ben Basat scored from the penalty spot in the 61st minute to double the lead, while Toure capped the scoring in the 67th to move Brest four points above the bottom three.
Evian 2, St Etienne 2
Annecy, France - St Etienne was denied the top spot in Ligue 1 on Saturday by Evian, which came from two goals down in the second half to claim a 2-2 draw.
PSG's 2-1 defeat to Rennes earlier in the day meant that a win would take St Etienne to the top of the league.
And after 28 minutes, the visitors looked to be on course as Max-Alain Gradel scored twice to give his team the lead.
However, Mohamed Rabiu scored early in the second half to pull a goal back for Evian, while the equalizer arrived 10 minutes from time when Aldo Angoula redirected a free kick from Daniel Wass past goalkeeper Stephane Ruffier.
St Etienne had one last chance to snatch the win, but Alejandro Alonso's powerful effort crashed against the crossbar.
Troyes 3, Nancy 3
Troyes, France - Nancy saw its winless run reach 12 games on Saturday at Troyes as the visitors allowed Benjamin Nivet to score twice in the final 10 minutes of a 3-3 draw.
Granddi Ngoyi had Troyes in front after 20 minutes, but Nancy quickly overturned its deficit to score three times in the final 13 minutes of the opening half.
Sebastien Puygrenier, Yohan Mollo and Andre Luiz each found the back of the net for Nancy, but Troyes stormed back late to capture a point.
Nivet reduced the deficit with a goal from 25 yards before he scored the equalizer from the penalty spot after Nancy's Joel Sami was whistled for a handball inside his own area.
Valenciennes 1, Montpellier 1
Valenciennes, France - Montpellier held on for a third successive draw on Saturday at Valenciennes as the defending champions were able to secure a 1-1 result despite playing more than 30 minutes with 10 men.
Valenciennes had won three of its last four entering the contest, but the hosts were behind after 15 minutes courtesy of a goal from Gaetan Charbonnier.
Gregory Pujol canceled out the strike for Valenciennes shortly before halftime, and the visitors went down to 10 men in the 57th minute when Jamel Saihi was sent off for a poor challenge on Gael Danic.
Montpellier was down a man but the visitors came closest to snatching the win as an overhead kick from Souleymane Camara hit the post.