Jeremy Pied's early goal claimed a shock 1-0 win for Guingamp over defending Ligue 1 champions Paris Saint-Germain on Sunday.
Pied headed in the only goal of the game in the 10th minute before Guingamp battened down the hatches and held on to their lead, with Jonas Lossl making a key late save to deny PSG dangerman Zlatan Ibrahimovic.
The win is a much-needed boost for strugglers Guingamp who moved up to 13th place with the victory, while PSG remained one point behind leaders Marseille, who could extend the gap if they take any points from Monaco at Stade Louis II in the late kick-off.
The victory was the second this week for Guingamp, who qualified for the Europa League round of 32 on Thursday, while it is the second successive defeat for PSG after they lost 3-1 at Barcelona in the Champions League.
However, Marseille could not capitalise as they went down 1-0 to AS Monaco in the late game.
Bernardo Silva netted the only goal of the game in the 67th minute to keep their one point lead over PSG with Lyon two further behind.
Lille finally solved their goalscoring problems, beating 10-man Toulouse 3-0 to earn three much-needed points.
Maxime Spano's first league start lasted only two minutes before he saw red for bringing down Divock Origi as the last man and though Marko Basa missed the resulting penalty, Lille were ahead five minute in anyway through Djibril Sidibe.
Ryan Mendes made it 2-0 early in the second half and Nolan Roux added the third to earn Les Dogues their first win in any competition since September, and one that lifts them away from the relegation zone.
St Etienne missed the chance to close the gap to third-placed Lyon after they were held to a 0-0 draw at Nice in a match which saw both sides reduced to 10 men in the first half.
St Etienne midfielder Ismael Diomande was sent off for his second bookable offence in the 37th minute for a poor tackle, while Nice midfielder Carlos Eduardo was dismissed shortly after for fighting.
Despite each being a man down, both sides created opportunities in the second half, although neither were able to find the breakthrough.
The result leaves ASSE three points adrift of Lyon while Nice remain in 11th place.