Bastia suffered their first defeat of the Ligue 1 season on Sunday, finishing with nine men as they lost 2-1 at Saint-Etienne.
Two wins and a draw from their opening three fixtures had seen Bastia make a promising start to the campaign.
However, the task of maintaining that promising run became more difficult when Alexander Djiku was sent off in the fourth minute for a studs-up challenge on Fabien Lemoine.
Saint-Etienne took advantage by taking the lead through Loic Perrin after 20 minutes - the unmarked defender tapping home from inside the six-yard box after the ball fell kindly for him from a corner.
A defensive mix-up opened the door for Gael Danic to equalise from a tight angle four minutes from half-time, but a wonderful 25-yard strike by Valentin Eysseric was a deserving match-winner.
Bastia proved unable to reel in their hosts for a second time and saw Francois Kamano sent off for clattering goalkeeper Stephane Ruffier in the 73rd minute.
Kamano looked to come off worse from the collision and was shown the red card as he lay stricken on a stretcher.
