Mainz' Lee Jae-sung scored on either side of halftime as the hosts stunned Bundesliga leaders Bayern Munich 2-1 on Saturday to snap their unbeaten league run this season.

South Korea international Lee struck four minutes before the break after pouncing on a defensive blunder by the lacklustre visitors.

Lee, 32, then doubled the hosts' lead on the hour, turning beautifully in the box to finish a superb attacking move that left the complete Bayern defence frozen to the spot.

It was also the first league loss for Bayern coach Vincent Kompany, who last week became only the third coach in Bundesliga history to have gone without defeat in his first 13 league games in charge.

The Bavarians, who pulled back a goal with Leroy Sané in the 87th, remain in top spot on 33 points, four ahead of Bayer Leverkusen, 2-0 winners at Augsburg.

Bayern, missing eight players to injury including top scorer Harry Kane, got off to a strong start, hitting the woodwork with Michael Olise in the sixth minute.

Mainz were dealt a major blow when Jonathan Burkhardt, who had scored in their previous four league games, was taken off injured after he fired wide following a powerful sprint in the 14th minute.

But it was the hosts who were more threatening, with Anthony Caci missing their best chance when his point-blank shot was blocked by Bayern keeper 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.

He then struck again with their first chance in the second half, turning well in the box to drill in after a quick six-pass move by Mainz.

Kompany's team never showed any desire for a comeback even after Sane's late goal, with Mainz comfortably holding on to their lead.