Borussia Dortmund have sacked Peter Bosz as head coach after their winless run stretched to 12 games in all competitions with the home defeat against Werder Bremen on Saturday.

Dortmund’s chief executive, Hans-Joachim Watzke, said: “Last night, in a conversation with Peter Bosz, we decided that we would release him with immediate effect. It was very emotional, but also respectful. On behalf of all at Borussia, I would like to thank Peter Bosz. We still consider him a great coach and person.”

Bosz took over the Bundesliga club in the summer but, despite a strong start, their form has deserted them and the Dutchman has come under increased pressure.

The 2-1 defeat against Werder on Saturday left Dortmund seventh in the Bundesliga, while they exited the Champions League after finishing third in Group H behind Tottenham Hotspur and Real Madrid, failing to win a match in the group stages.

The club announced that the former Cologne manager Peter Stöger would take charge of the team until the end of the season. “I’m really happy to be coach of this team and to be in this stadium,” Stöger said.

The Austrian was sacked by Cologne this month, but only after a four-year tenure in which he guided them to promotion from the second tier and then to fifth place in the league last season to earn European football.

A dismal start to this campaign, in which they took only two points from the first 13 matches, cost Stöger his job but Dortmund hope he can have a similar impact on their fortunes as he did when he first arrived in Cologne.

“In four years, Peter Stoger has developed the team excellently at Cologne,” said Dortmund’s sporting director, Michael Zorc.

Stöger is due to oversee his first training session later on Sunday, with his first match coming on Tuesday night, away against Mainz.