Nancy have been relegated back to Ligue 2 after just one season in the French top flight, despite earning victory over Saint-Etienne on the final day of the season.
Les Chardons started the day bottom of the pile but won 3-1 at Stade Marcel Picot on Saturday evening, only for results elsewhere to go against them.
Bastia were two points better off than Nancy heading into the finale, which saw five teams in danger of the drop, but they lost 1-0 to Marseille - Bafetimbi Gomis scoring the crucial goal - to go down as the bottom-placed side.
Caen and Dijon were the other two sides embroiled in the exciting battle at the bottom, with the former scoring a late goal away to Paris Saint-Germain to draw 1-1 and maintain their top-flight status.
Elsewhere, Marseille's win over Bastia sees them finish fifth in the table, while outgoing Lyon striker Alexandre Lacazette netted twice in a 3-3 draw with Nice to bow out with 100 league goals for the club.