Nice's run of games without a win in Ligue 1 now stands at four after Reims held them to a 1-1 draw at Stade Auguste-Delaune.
Valere Germain ended a run of three matches without a goal with just six minutes on the clock, converting at the second attempt following Olivier Boscagli's cross.
But Diego Rigonato struck a penalty 14 minutes from time after Vincent Koziello was penalised for handball, denying Nice the chance to move level on points with fourth-placed Monaco.
Lille, meanwhile, closed the gap to eighth-placed Lorient to two points after their 3-0 victory over Sylvain Ripoll's side.
A goal in each half from Eric Bautheac and a late third from Djibril Sidibe inflicted only a third defeat in 13 away games for Lorient and extended Lille's impressive recent domestic run to three wins on the bounce.
Toulouse were denied a valuable victory away to Nantes thanks to Emiliano Sala's late headed goal secured another 1-1 draw.
Aleksandar Pesic gave the visitors the lead shortly after half-time and they looked likely to hold on to the three points.
But Sala's emphatic header with four minutes to play ensured a share of the spoils for Nantes, and Toulouse finished the game with 10 men after Issa Diop was shown a straight red card in stoppage-time for violent conduct.
Bottom-club Troyes are still waiting for their first win of the season after being held at home 1-1 by Bastia, who move into 17th place with the point.
Seko Fofana put the visitors ahead midway through the first half but Troyes levelled thanks to Jimmy Cabot's finish just before hour mark.
Guingamp drop beneath Bastia into the relegation zone after Montpellier came from behind to beat them 2-1 at the Stade de la Mosson.
Sloan Privat headed the visitors into the lead on 32 minutes but Nicolas Benezet's dismissal for a second yellow just two minutes later handed momentum to the home side, who levelled just after the break through Souleymane Camara.
Camara teed up Casimir Ninga to complete the comeback and move Montpellier into 14th.
