Mainz have parted company with head coach Achim Beierlorzer after his side lost their opening two games of the 2020/21 Bundesliga campaign whilst conceding seven goals.
The 05ers began the new campaign with a 5-1 win over minnows Havelse in the DFB Cup first round, but were soundly beaten 3-1 and 4-1 by RB Leipzig and promoted VfB Stuttgart on Bundesliga Matchdays 1 and 2 respectively.
Assistant coach Jan-Moritz Lichte will take charge in an interim capacity until further notice.
"We sat down to assess the situation, and looked at how we can give the team fresh impetus in the short term and further down the line," explained Mainz sporting director Rouven Schröder. "The result of these open and honest talks was a parting of ways with Achim Beierlorzer.
"We successfully beat relegation, working together during what was a difficult time. Achim Beierlorzer deserves our respect for his efforts."
Beierlorzer becomes the second coaching casualty of the 2020/21 season, after Schalke parted ways with David Wagner in the aftermath of Matchday 2.
The 52-year-old - who replaced Sandro Schwarz in mid-November 2019, nine days after losing his job at Cologne - oversaw nine wins, four draws and 13 defeats.
Mainz finished 2019/20 in 13th place, six points clear of the relegation play-off spot, but head to Union Berlin on Friday without victory in three league matches dating back to Matchday 33 of last season.