Borussia Dortmund captain Marcel Schmelzer has backed Peter Bosz and told kicker: "It's our duty to give something back to the coach."
BVB have dropped from first to third in the Bundesliga and all but crashed out of the Champions League during a turbulent seven-game run.
Bosz has come under fire for his high defensive line in a 4-3-3 system, and questions have been raised about whether the former Ajax man can turn things around.
The Dortmund hierarchy have backed Bosz and captain Schmelzer did the same, saying: "With his calm and analytical approach, he conveys a good feeling to the team. He knows what he does.
"That he sometimes protects us should not lead to us hiding behind him. It's our duty to give something back to the coach.
"We players should not hide behind the nervous discussion about system and tactics which is led in public. We must perform again in the situation we are in right now."
In the last four league games, Dortmund have conceded 12 goals and taken only one point in a draw at Frankfurt.
But Schmelzer said: "Quality? I don't think that's the problem. It's a mix of several things. Especially with the young players, declining confidence is of concern.
"But the lads must go through the process that up is not the only way and that they sometimes don't make the squad. They will grow and come back stronger.
"We don't have one big problem, but rather several smaller ones."
Schmelzer said those problems included "the not well attuned back four," "the lack of coordination" between the lines and "the lack of naturalness to build pressure on opponents already in attack."
Citing Dortmund's injury woes, especially at the back, he added: "The midfield hangs in the air between those two lines."
Meanwhile, BVB president Reinhard Rauball said Dortmund remained on course to reach their goals this season.
"We did not say we must win the league, but rather qualify for Champions League," he said.
"I belong to those who have a critical view of what needs to be viewed critically. But I also belong to those who trust those who are in charge of the sporting side, and that has not been shattered."