Letsch departs with Bochum in 15th place, three points clear of safety, having secured their top-flight status with a 14th-place finish last season.

Heading into Matchday 28, the Ruhr club had four defeats and a draw in their past five matches, but looked set to end that run, leading Cologne until the final minute of the match. However, an equaliser from Steffen Tigges and a stoppage time winner from Luca Waldschmidt left the team in danger of heading into the bottom three.

"We haven't managed to stabilise ourselves in the long term and have not been as good as we could have been in recent matches," said sporting director Marc Lettau in the club's official statement. "We can still stay up under our own steam. The team has the quality to hold its own in the Bundesliga, which is why we want to provide a decisive impetus for staying up by making the switch."

Watch: Highlights from Bochum's late defeat in Cologne

BOC Bochum Bochum - FCH Heidenheim Heidenheim

Bochum part ways with Thomas Letsch