Marcel Gaus netted the winner for the hosts deep into second-half stoppage time to complete a sensational comeback and trigger wild celebrations from the home crowd as the Bayern players looked on in complete shock.
Mueller has apologised to their fans and admitted the 5-0 thrashing at Moenchengladbach in the German Cup was the worst defeat he has experienced.
On April 19, many important events that changed the world map took place.
Joshua Kimmich edged Bayern Munich into the German Cup semi-finals with the only goal in a 1-0 win at Schalke 04 on Tuesday.
Good news has been in short supply for Schalke 04 this season and while they suffered another blow on Wednesday with the death of their former general manager Rudi Assauer, the emergence of Ahmed Kutucu has given fans cause for hope ahead of their trip to
Bayern Munich succeeded in securing an important victory over RB Leipzig (5-4) with penalties after they ended the full time with a draw (1-1).
Guinean player Naby Keïta has been sent off against Bayern Munich in German Cup.