The storm on Europe's throne proclaimed, demonstrated by Bochum: four days before the round of 16 first leg in the Champions League, serial champions Bayern Munich suffered an almost historic Bundesliga humiliation.
At the end of a turbulent week, the leaders of the table lost 2: 4 (1: 4) to promoted VfL Bochum, pursuers Borussia Dortmund can move up to six points on Sunday.
World footballer Robert Lewandowski (9th) brought Julian Nagelsmann's star selection, who is challenged in the premier class at Red Bull Salzburg on Wednesday, into the lead.
But intrepid Bochum duped the favorites with goals from Christopher Antwi-Adjei (14'), Jürgen Locadia (38'/penalty), Cristian Gamboa (40') and Gerrit Holtmann (44') before the break.
Lewandowski (75th) made it exciting again.
VfL, which took a big step towards staying in the league, brought Bayern back to a Bundesliga bankruptcy as the first promoted team since 1. FC Kaiserslautern in August 2010.
Bayern Munich had last conceded four goals in the first half in 1975 at Eintracht Frankfurt (final score 0:6).
The 0:7 in the first leg on September 18th was the heaviest Bundesliga defeat for VfL - for Reis it was a pivotal experience.
"Bayern showed us what's missing," said the VfL coach.
Both teams started without their regular goalkeepers.
Bochum's Manuel Riemann has been infected with Corona, national keeper Manuel Neuer is expected to be absent from FC Bayern for several weeks after knee surgery.
Bayern coach Nagelsmann relied on Sven Ulreich in goal, Niklas Süle played in front of him in the center of defence.
The national defender will move to BVB on a free transfer in the summer, as announced on Monday.
But that was "no reason to put him in the stands," said Nagelsmann: "I trust him completely."
Before kick-off, the 8,500 spectators had to do without Herbert Grönemeyer's goosebumps anthem "Bochum" - a power failure in the entire Grumme district initially paralyzed the technology and the floodlights.
VfL was bursting with energy, the promoted team started briskly against the series champions, who were offensive in the 4-1-4-1.
Bayern answered typically: first chance, first goal.
Lewandowski switched first from a Kingsley Coman cross and scored his 25th goal of the season.
Anyone who now believed in a "normal" course of the game was disappointed: in the 14th minute, VfL surprised the big favorites with a counterattack, Holtmann left Dayot Upamecano and played into the centre, where Antwi-Adjei gave the sluggish Süle the disadvantage.
Bayern fought for dominance, but lacked freshness and esprit against the aggressive and agile Bochum side.
Upamecano jumped the ball in his own penalty area, Bochum's winter signing Locadia overcame Ulreich from the point with a bit of luck.
Bochum was now intoxicated.
Locadia moved in from the right and hit the corner, Holtmann scored the next dream goal from the left.
The half-time period brought back memories of Bochum's game of the century in 1976. Back then, VfL even led 4-0 against FC Bayern at half-time - and lost dramatically 5-6.
Nagelsmann reacted, scored another six in Corentin Tolisso and took the overwhelmed Upamecano off the field.
The pressure grew, a Lewandowski free kick (86th) hit the crossbar.