Lyon failed to keep up their modest pressure on Paris Saint-Germain as they suffered a 3-1 defeat to Rolland Courbis' Montpellier.
An error-strewn display from Hubert Fournier's team consigned them to a fourth defeat in five games in all competitions and could see them fall 16 points adrift of the defending champions.
After an open start, Maxime Gonalons turned Jerome Roussillon's cross into his own net before William Remy released Rodrigue Ninga to net the second after 11 minutes.
Montpellier scored their third three minutes after the break, Rafael cheaply conceding possession with Ninga taking full advantage of the right-back's error.
Their misery was compounded when Milan Bisevac's weak challenge failed to stop Ryad Boudebouz racing through to set up Souleymane Camara for the fourth, with Rachid Ghezzal's fine free-kick offering scant consolation.
