Florian Thauvin scored twice inside just 17 minutes and Bastia handed Bordeaux its first loss in Ligue 1 this season, 3-1, on Sunday at the Stade Armand-Cesari.
Thauvin scored in the sixth and 17th minutes and, after Yoan Gouffran notched a goal on the half-hour for Bordeaux, Wahbi Khazri secured the win 11 minutes after half for Bastia.
Promoted Bastia extended its undefeated streak to four matches, and climbed to 11th place on 14 points after 10 matches.
Bordeaux started the season unbeaten in nine matches, securing three victories along with six draws, but sits just eighth on 15 points after its first loss.
Lorient 4, Ajaccio 4
Lorient, France - Jeremie Aliadiere scored twice in the second half and Gilles Sunu scored four minutes into stoppage time, as Lorient overcame a three-goal, second-half deficit to draw Ajaccio, 4-4, on Sunday at the Stade du Moustoir.
Eduardo scored twice and Chahir Belghazouani, Adrian Mutu also scored goals in the first half for Ajaccio, but Lorient tacked on three to a first-half strike from Wesley Lautoa to earn a share of the points in the Ligue 1 match.
Aliadiere started the comeback in the opening minute of the second half, added a second goal in the 79th, and Sunu left it late as Lorient erased the memory of a 6-1 loss at Valenciennes last weekend.
Winless in five straight, Lorient remained in the top half on 15 points, while Ajaccio tied its second straight during a three-game winless streak and has 11 points and sits just outside the top half.