Paris St Germain coach Thomas Tuchel accepts his side again made "too many individual mistakes" as they followed up their Coupe de France defeat with a 3-2 loss at Montpellier.
The French champions were beaten in a penalty shootout by Rennes on Saturday, with forward Kylian Mbappe shown a red card for a studs-up challenge.
PSG, though, looked to have produced the required response on their return to Ligue 1 action at Stade de La Mosson, taking a 12th-minute lead through Ambroise Oyongo's own goal.
Montpellier, seeking to keep alive their own European qualification hopes, soon equalised when Presnel Kimpembe put the ball into his own net – the defender having also scored an own goal in the cup final.
A clever finish from Angel Di Maria just after the hour looked to have been enough for all three points, but with only 10 minutes left, Andy Delort broke clear to equalise.
There was still enough time for Montpellier substitute Souleymane Camara to snatch a dramatic victory following poor decisions – first by PSG goalkeeper Gianluigi Buffon and then defender Leandro Paredes, who was robbed of possession on the edge of the area after taking a quick pass from the veteran Italian.
"We're disappointed, but we didn't play badly," Tuchel said at a press conference reported by the club. "We deserved to be ahead, but we made too many individual mistakes. That's been the case for a number of matches now, and that's why we are losing."
PSG came into Tuesday's game with a 16-point lead over second-placed Lille and the title already sewn up.
Tuchel, though, maintained he did not want to believe his team had "slackened off".
The German continued: "It's something we've seen for a number of years, that the team loses intensity at the end of the season.
"It's something I can understand, but it's not something I want to accept."
Defender Marquinhos told French broadcaster Canal+ afterwards that the team were "in a difficult moment".
Marquinhos continued: "We show our bad face. In the field, one must be more mature. We need to change our mindset, to play as a team, both with the ball and without.
"There are many things that need to be improved. We will talk in the locker room to get out (of it).
"In situations like that, you have to be much stronger than when everything goes for you."
Montpellier coach Michel Der Zakarian celebrated signing a contract extension with a memorable performance, as they moved to within five points of fourth-placed Saint Etienne.
"The victory is well deserved," he said at a press conference. "We were irreproachable in our state of mind and we made the right choices."
Asked for his thoughts on the current problems for PSG, Der Zakarian said: "It is a great team, great players, a good coach.
"They live a difficult time, but it happens to everyone."
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