Juergen Klopp will leave Borussia Dortmund at the end of the season after a seven-year reign as coach which delivered two Bundesliga titles and a Champions League final.
The 47-year-old told a news conference on Wednesday that he felt he was no longer the right man for the job, despite a contract supposed to last until 2018.
In a surprise decision, Klopp said it was time for the club to have a change and said he had not decided whether he would take a year out of the game or not.
"I've always said that I would say it if I'm not the perfect coach for this extraordinary club," Klopp told reporters at the emotionally-charged news conference.
Sitting next to him, club CEO Hans-Joachim Watzke and sports director Michael Zorc were close to tears.
"Dortmund need a change. It has nothing to do with the current sporting situation," he said.
"I picked this time for my announcement so as not to create any time pressure as was the case in the last few years with some player decisions."
"I definitely believe this is completely the right decision. Sometimes big heads must roll and today it was mine. There was never any rift with the team."