A mistake from Anthony Lopes contributed to a 3-0 defeat that leaves the champions needing just a point to defend their crown.
Paris Saint-Germain is within a point of retaining its Ligue 1 title after closest challengers Lyon went down to a shock 3-0 defeat at Caen on Saturday.
PSG romped to a 6-0 win over Guingamp on Friday and Lyon collapsed as it tried to respond, with Nicolas Benezet netting twice in the space of four minutes as halftime approached - the opener aided by an error from Lyon goalkeeper Anthony Lopes.