PSG – crowned champions of the French top flight on Wednesday – won 3-1 at third-placed Lille to keep the race for the final UEFA Champions League place alive.
But the real drama was at the other end of the table as Herve Renard's Sochaux won again.
They sat six points adrift of safety in late March but a seven-match unbeaten run – of which four have been wins – have given Sochaux every chance of remaining in Ligue 1 with one match remaining.
Their latest triumph means they are now just one point behind the 17th-placed Evian TG, while Montpellier, Guingamp and Nice could also be relegated on the final day of the season.
Sochaux's latest win came thanks to a late winner from former Southampton striker Emmanuel Mayuka.
Marseille loanee Jordan Ayew put Sochaux in front after 33 minutes but Paul Ntep came off the bench to level for Rennes with 18 minutes left.
Mayuka was to be the hero though, converting Sebastien Roudet's assist in the 77th minute.
Evian will now be looking over their shoulder despite a 2-0 home win over Nice in which Kevin Berigaud and Nicolas Benezet both scored.
The loss leaves Nice two points clear of safety.
Guingamp are also two points ahead of Sochaux after Claudio Beauvue and Mustapha Yatabare scored in a 2-0 triumph over Toulouse.
And 2012 champions Montpellier are still not sure of their league status next season after a 2-0 home defeat to Bastia.
Sambou Yatabare and Wahbi Khazri both netted for the winners.
At the other end of the table, PSG won well at Lille but had their triumph soured by an injury to Yohan Cabaye.
Marquinhos opened the scoring for PSG in the 41st minute, shortly after Marvin Martin had been dismissed for a dangerous challenge on Cabaye.
France international Cabaye had to be stretchered from the field under the closed roof of Stade Pierre-Mauroy, casting doubt over his involvement in the FIFA World Cup.
Lucas Moura put PSG two goals up in the 65th minute, before substitute Blaise Matuidi grabbed his fifth league goal of the season late on.
The league's previous record for a single season was 84 points – set by Lyon in 2005-06 – and PSG now stand two points clear of that marker with a match still to play.
Jonathan Delaplace grabbed a stoppage-time goal for Lille, whose bid for UEFA Champions League football will now go down to the wire after fourth-placed Saint-Etienne cruised to a 3-1 win at Nantes to close the gap between the sides to two points.
Other results saw Marseille draw 1-1 at Bordeaux while Lyon slumped to a 1-0 home defeat against Lorient.
Already-relegated Ajaccio beat Reims 2-1 but the news was not as good for Valenciennes, who will also play in the second tier next season, as they lost 2-1 at home to Monaco.
