Rennes keeper Benoit Costil saves a penalty as Les Rouges et Noirs defeat Nancy 3-1 at the Stade Marcel Picot.
Nancy remain rock-bottom of Ligue 1 following a 3-1 defeat at home to Rennes.
The result means that they have won just once in 12 outings, leaving them five points away from safety.
Rennes took the lead in the 21st minute through Melvut Erding, who headed past Guy N'Dy from Chris Mavinga's cross.
However, the hosts drew level five minutes after half-time, when Simon Zenke outfoxed Jean-Armel Kana-Biyek before finding the top corner.
Romain Alessandrini restored Rennes's lead in the 74th minute with a stunning left-footed volley to leave N'Dy with no chance.
Nancy were given a route back inot the match when John Boye upended Zenke and the referee pointed to the spot.
Paul Alo'o Efoulou stepped up to take it but Benoit Costil made himself a hero, saving superbly in the bottom-right corner.
The hosts were made to pay six minutes from time when Jonathan Pitroipa latched onto Massadio Haidara's pass back, lifted the ball over N'Dy and headed into an empty net.
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