New Saint-Etienne coach Jean-Louis Gasset was unable to inspire his new side as they slumped to a 2-1 defeat at Guingamp.
The former assistant's appointment - following Oscar Garcia's resignation last month - was only announced an hour before Wednesday's Ligue 1 game, which stretches the club's winless run in the league to 11 games.
Hernani Azevedo Junior had given them hope of securing a rare win with a 67th-minute opener, but they were pegged back soon after by Nicolas Benezet and then suffered late heartbreak as Jimmy Briand scored in the fifth minute of injury time to snatch all three points for Guingamp.
ASSE sit 16th in Ligue 1, two places and one point above the relegation play-off spot.
2-1 TERMINÉ à Guingamp. Réduits à dix dès la 22ème minute de jeu mais solidaires, les Verts s'inclinent de la manière la plus cruelle possible. December 20, 2017
