Hoffenheim have sacked coach Markus Babbel after losing 4-1 at home to Werder Bremen on Sunday.
Babbel has been under pressure after a poor run of form left the club - who had targeted European qualification - languishing in 16th place in the Bundesliga, two off the bottom, having conceded 36 goals, the most of any club in the league.
He was given a vote of confidence after last week's 4-2 defeat at Nurnberg, but had won just seven of his 29 matches in charge.
The former Germany international defender only took over in February 2012 but, after his team had taken only six points from their last ten games, the club decided to dispense with his services.
Announcing the move after a board meeting on Monday, general manager Andreas Muller said: "I have decided, after careful consideration and in consultation with the management and the shareholders, to make a change.
"Our increasingly threatening situation and the associated negative trends have left me no choice. We must now press the reset button and start over. We all have to work together to get out of this precarious situation.
"Looking back at the last couple of games, we had the chance to turn things around. But we did not find any answers, and so it is normal to take those measures."
Reserve coach Frank Kramer will become caretaker until the winter break, and Muller added: "We will not be pressured.
"We will see how perform in those games, but I don't want to rule out that he remains Hoffenheim coach for a while." Kramer said he was confident he could handle a "difficult" task. Speaking after Sunday's defeat, Babbel had said: "I am the last to give up" but Muller increased speculation over his future, telling reporters: "I cannot say if we will continue to work with him. The situation is awkward."
Hoffenheim patron Dietmar Hopp, on holiday in Florida, had given Muller the authority to make major decisions in his absence.