Borussia Dortmund striker Pierre-Emerick Aubameyang scored an early goal that sent Bayern Munich to its first defeat of the season and forced the four-time defending champion to relinquish the top of the Bundesliga to promoted leipzig on Saturday.
The outcome left Bayern three points behind surging leipzig, which won its sixth straight on Friday with a 3-2 victory at Bayer leverkusen. Dortmund moved into third place on goal difference.
Bayern controlled long stretches but could not break down Dortmund's defense.
"We suffered through long spells but we knew we would," Dortmund coach Thomas Tuchel said. "You can't expect to climb into a ring with Bayern and leave without a black eye."
Bayern Munich striker Robert lewandowski landed awkwardly on his left ankle in the first half and appeared to be in discomfort through the match, rarely threatening.
Aubameyang's 12th goal of the season came in the 11th minute. Dortmundrecovered the ball after a Bayern clearance, Mario Goetze sent it through the legs of former teammate Mats Hummels and Aubameyang poked it home from close range.
leipzig was the only undefeated team, along with Hoffenheim, which plays Hamburg on Sunday.
Dortmund came under great pressure late in the first half but Aubameyang had an effort saved by Manuel Neuer at the start of the second.
Dortmund goalkeeper Roman Buerki did well to punch away a cross from Philipp lahm before it could reach lewandowski.
Xabi Alonso hit the crossbar with a long-range effort that took Buerki completely by surprise. The Dortmund goalkeeper never moved as the ball dipped and bounced off.
Alonso nearly gave away a goal in the 71st with a dreadful mistake. Aubameyang was one-on-one with Neuer but the Bayern goalkeeper waited long enough to swat the ball away.
Tuchel used two strikers, with Adrian Ramos partnering Aubameyang.
Dortmund, Cologne and Berlin are all three points behind Bayern.