Monaco suffered a 1-0 defeat away to Lorient in their Ligue 1 round 7 clash. It marked the first league defeat of the season for the Monegasques, coming just three days after their 2-1 victory over CSKA in the Conference League group stage.
A 61st-minute penalty from Noah Cadiou sealed a vital victory for the hosts. Seven minutes before the end of normal time, Dembo Sylla fired an effort towards the visitors' goal, only to be denied by the woodwork.
Monaco sit fourth in the standings on 14 points, level with leaders Paris Saint-Germain, with Paris FC and Lille also ahead of Filipe Luis' side.
Lorient climbed to seventh place after securing their second consecutive win. Les Merlus have now collected 11 points, sitting level with Lyon ahead of their meeting with Nice.