Lens beat Ligue 1 leaders Paris St Germain 3-1 on Sunday to give the champions their first league loss of the season, narrowing the gap at the top between the two teams.
PSG were without Neymar, who was suspended after getting sent off against Strasbourg on Wednesday, and Lionel Messi who is continuing his post-World Cup recovery.
The result means Christophe Galtier's side are on 44 points from 17 games, four points ahead of Lens in second.
The hosts took an early lead after five minutes when a deflection from PSG keeper Gianluigi Donnarumma went to an unmarked Przemyslaw Frankowski, who volleyed the ball into the open net.
Hugo Ekitike equalised for PSG three minutes later when the striker reached a cross before Lens goalkeeper Brice Samba and tapped the ball in.
Lens striker Lois Openda restored his side's lead in the 28th minute when he got a through ball from Seko Fofana and ran into the box, where he beat defender Marquinhos before finishing into the lower-right corner of the goal.
French forward Alexis Claude-Maurice made it three for Lens two minutes into the second half to seal the win.
Sherfane Rutherford struck an unbeaten half-century and Gudakesh Motie produced a brilliant display of spin bowling as West Indies thumped England by 30 runs in a Twenty20 World Cup Group C encounter on Wednesday.
Australia launched their Twenty20 World Cup campaign with a commanding 67-run victory over Ireland in Colombo on Wednesday, powered by four-wicket hauls from Nathan Ellis and Adam Zampa.
Tottenham Hotspur have sacked manager Thomas Frank after eight months in charge, the Premier League club said on Wednesday, after a woeful run of results left the north London club hovering five points above the relegation zone.
South Africa survived Kagiso Rabada's final-over meltdown against Afghanistan and then a double Super Over drama before prevailing in a heart-stopping Group D match of the Twenty20 World Cup on Wednesday.
Pakistan opener Sahibzada Farhan has hit a swift half-century as the 2009 champions comfortably beat the US by 32 runs on Tuesday, clinching their second straight Group A win in the Twenty20 World Cup.