Thomas Tuchel concedes Paris Saint-Germain are not performing as he would hope and are lacking confidence, while he believes Marco Verratti's absence does not help.
PSG are five points clear of nearest challengers Marseille at the top of Ligue 1, with a game in hand, and they are through to the last 16 of the Champions League as Group A winners ahead of Real Madrid.
But Tuchel has not been enthused by his side's recent performances, even with comfortable 2-0 wins over Lille and Nantes sandwiching a gripping draw at Madrid.
Star midfielder Verratti played 90 minutes against Madrid on November 26 on his return from a knee injury, but he missed Wednesday's victory over Nantes with a thigh issue and will not feature again at Montpellier on Saturday.
Ander Herrera is out, too, with Idrissa Gueye also a doubt in a further blow to Tuchel's options in the centre of the pitch.
Tuchel said of Verratti's absence: "Of course, it changes things. He gives quality and personality to the team, he always gives 100 per cent, he has a lot of influence, and he's always a positive guy.
"It is clear we are missing him, but we must be careful with him. He played 90 very hard minutes against Madrid, but we expect him in the team against Galatasaray."
Tuchel preferred not to go into detail on the reasons for PSG's struggles, although he claimed their performances in training prove the quality is there.
"It's like this: we are in a phase where we are not playing our best football," he acknowledged.
"We want to talk about performances, not just results. It is up to us to analyse and we must admit that we are in a phase where everything is not easy.
"There are reasons, but I do not want to talk too much. This is something that has lasted for several weeks. We have ideas, and I said honestly [after Nantes] that we were not satisfied with the performances.
"But I remain totally positive and it is good that we play again tomorrow."
He added: "I am convinced that there is not just one reason. And why am I positive? Because I see my team every day in training.
"It's a little weird because we show a lot of quality and intensity during training. We have had 20 to 23 players for two or three weeks in training.
"We have gained intensity during the sessions but cannot necessarily show it during the matches. It's a little weird.
"The team has a good state of mind every day. Yesterday again, they were extraordinary. The guys who did not play a lot were great. The guys are disappointed they did not play but they give everything, they are together.
"We have to show it during the matches, but we must not force it. We may be lacking a little bit of confidence, but we do not lack quality."