Anthony Le Tallec netted a brace for the home side, while Gael Danic and Foued Kadir also got on the scoresheet at the Stade du Hainaut.

Jordan Ayew scored a late consolation for Marseille, who had won their opening six matches and conceded just one goal before travelling to Valenciennes.

"It's a heavy defeat, when we went in at halftime 3-0 down the game was over for us,'' Marseille manager Elie Baup said.

"After their first goal we had some chances, we could have got back to 1-1, but we couldn't do it. When you lose like that, it means that very little went right.''

Lyon suffered their first defeat of the season after they conceded two second-half goals at home to championship rivals Bordeaux.

Following a goalless first-half, Bordeaux took the lead through Benoit Tremoulinas and the visitors maintained their unbeaten start to the campaign with a second goal courtesy of Cheick Diabate.

The results moves Bordeaux up to fifth, while Lyon drops down to third, four points adrift of leaders Marseille.

Elsewhere, Saint Etienne and Reims played out a 0-0 stalemate.