Thomas Tuchel said Paris Saint-Germain "lack players" as he vented his frustration with the team's depth following their Ligue 1 humbling against Lille.
PSG had the chance to wrap up their sixth title in seven seasons on Monday (AEST) but the French club's celebrations were put on hold following a humiliating 5-1 defeat.
Lille crushed 10-man PSG after Juan Bernat – who equalised following Thomas Meunier's own goal that gifted the hosts the lead – was sent off in the first half at Stade Pierre-Mauroy.
Nicolas Pepe, Jonathan Bamba, Gabriel and Jose Fonte struck as PSG conceded five goals in a Ligue 1 match for the first time since 2000.
PSG star Kylian Mbappe said the team "played like beginners" but head coach Tuchel told Canal+: "No, it's too easy to say like Mbappe that we lacked personality, we were in control.
"We made a good start to the match, with four goals, two for us and two offside. They didn't have any chances in the first half, and there was [Thilo] Kehrer's opportunity in the beginning of second half.
"With 10 players it became complicated, we played with sick players who should not have played. It's not possible to have only 16 players.
"This defeat shows something else, we have shortcomings every time. On the contrary, this game shows our mentality, contrary to what everyone thinks.
"To win here, we would have needed more qualities. Given the circumstances, we had a good game, I have to protect my players At 10, it became extra hard. Win in Nantes? I do not think we're going to win, maybe we'll go there with 13 players... Tonight's match showcases everything we've done well this season.
"Paris lack players. Yes, we're missing Lass Diarra and Adrien Rabiot. Everyone sees that. And I will tell that to the president, yes. Nobody said anything before because we were winning. Now, everyone has to think."