Werder Bremen demolished Bayern Munich in their own back yard on Saturday to inflict a first defeat on coach Jurgen Klinsmann since his arrival at the Allianz Arena this summer.
Goalkeeper Michael Rensing also tasted his first loss with the defending champions on what was a forgettable day for the new Bayern number one.
He could do little to stop Markus Rosenberg from putting Bremen ahead on the half-hour mark while Ronaldo Naldo doubled the visitor's lead on the stroke of half-time.
Mesut Ozil then added a third after 54 minutes before Claudio Pizarro threaded the ball through Rensing's legs to score on his return to Munich five minutes later.
Rosenberg then accepted a gift from Rensing for the fifth in the 67th minute before two late goals from Tim Borowski finally gave the home fans something to cheer about.
Bayern came into the game in confident mood on the back of three consecutive wins, including a successful start to their Champions League campaign against Steaua Bucharest in midweek.
But the alarm bells were ringing as early as the third minute when Diego's free-kick caught Rensing off guard and only just missed the post.
Rosenberg then set the wheels in motion for Bremen after 30 minutes when he stole in between Martin Demichelis and Daniel Van Buyten to collect Ozil's pass and dispatch it past Rensing from just inside the penalty area.
Lukas Podolski almost scored an equalizer soon after, but he blazed his shot over the crossbar.
It was one-way traffic from then on with Naldo on hand to convert a shot from Ozil in the last minute of the first half.
The lively Ozil then added his name to the score sheet in the 54th minute when he shrugged off the attentions of Bayern substitute Massimo Oddo and drilled a shot into the top left-hand corner of the goal.
Pizarro was making his return to Munich just over a year after leaving the club to join Chelsea and he got in on the act in the 59th minute.
The Peruvian received the ball from Rosenberg with his back to goal, but turned and shot in an instant with the ball going through Rensing's legs on its way into the back of the net.
Rosenberg then grabbed his second of the game after a mistake from Rensing. The Bayern keeper missed his punch to leave the Swedish striker with an easy tap-in to make it five.
Bayern showed some fight late on with former Bremen midfielder Borowski pulling a goal back from Oddo's pass in the 71st minute before he scored again five minutes from time, placing his shot in from the edge of the penalty area.
But the damage had already been done as Bremen ran out comprehensive winners.
