MAINZ, Germany (Reuters) -Bundesliga leaders Bayern Munich went down 2-1 at Mainz 05 as their unbeaten league run this season was ended after Lee Jae-sung scored either side of the break on Saturday.
South Korea's Lee struck four minutes before halftime after pouncing on a defensive blunder by the lacklustre visitors.
The 32-year-old then doubled the hosts' lead on the hour, turning beautifully in the box to finish a superb attacking move that left the Bayern defence frozen to the spot.
It was the first league loss for Bayern's Vincent Kompany, who last week became only the third coach in Bundesliga history not to suffer defeat in his first 13 league games in charge.
"We played against a team with a lot of life and spirit and they were prepared to fight for every moment," Kompany said.
"From our side there was not a lack of fighting. We did that to the best of our ability. Today we were not at our best."
The Bundesliga goes into a three-week winter break after next week's round of matches.
"This game, we can't play it any more. It's done," Kompany said. "We'll use it to build a fire for next week. That's the only way to give an answer. This game in Mainz this year we can't win it but in the future ... we're looking forward to it."
The Bavarians, who pulled a goal back through Leroy Sane in the 87th minute, are top on 33 points, four ahead of Bayer Leverkusen, who won 2-0 at Augsburg. Mainz are sixth with 22.
PLAYERS MISSING
Bayern, who were 5-1 winners over Shakhtar Donetsk in the Champions League earlier in the week, were missing eight injured players including top scorer Harry Kane.
They still got off to a strong start, hitting the woodwork through Michael Olise in the sixth minute.
Mainz, who lost 4-0 to Bayern in the German Cup in October, were dealt a major blow when their top scorer Jonathan Burkardt, with 10 league goals this season, was taken off injured after he fired wide following a powerful sprint in the 14th minute.
It was the hosts, however, who were more threatening, with Anthony Caci missing their best chance when his point-blank shot was blocked by goalkeeper Daniel Peretz.
Lee did better four minutes before the break, slotting in from a cross that first slipped past Bayern's Kim Min-jae and Olise.
The South Korean then struck again on the hour with Mainz's first chance of the second half, turning well in the box to drill home after a quick six-pass move.
Bayern never looked like completing a comeback after Sane's late goal, with Mainz comfortably holding onto their lead.
(Reporting by Karolos Grohmann; editing by Clare Fallon and Ken Ferris)
