The Gelzenkirchen club, which finished in fourth place in the Bundesliga, announced on Wednesday that Rudi Assauer had resigned from his position as general manager.
Assauer had been criticized for some time for his disagreements with former team coach Ralf Rangnick, who was dismissed from the team this winter for unclear reasons despite the team's good performance.
Assauer, considered one of the most colorful personalities in the Bundesliga, had previously stated that he would resign from his position as general team manager after the season in order to become the club's president.
However, due to disagreements with the chairman of the club's supervisory board Clemens Toennies, Assauer has now announced that he is leaving the team and does not intend to take on any role within it.