Bayern Munich's injury hit squad wen were well beaten by in-form Borussia Monchengladbach as Jupp Heynckes's unbeaten record since his return to the Bundesliga champions was ended in a limp fashion.
The first half was a mostly tense affair, with Rafael missing a golden opportunity to open the scoring after a defensive error as the Brazilian sliced his shot horribly wide. With the Bundesliga champions failing to give their hosts anything to think about, the hosts patient approach paid off when Niklas Sule handled Thorgan Hazard's flick, winning Gladbach a penalty.
The Belgian, who is also the younger brother of Chelsea's Eden, stepped up and smashed the spot kick home despite Sven Ulreich getting a strong hand on the attempt. Bayern's open play improved and they came close to levelling when Robert Lewandowski neatly controlled Arturo Vidal's header but his improvised back heel smacked off the post.
It was the free scoring Pole's best chance in an isolated display, and just before half time Gladbach worsened Bayern's evening when some extremely lacklustre defending allowed Lars Stindl to run into the box and his deflected shot fell perfectly for ex-Dortmund right-back Matthias Ginter to tap into an empty net and send the home fans at Borussia Park wild.
Like the first half, the second period started slowly as Gladbach frustrated their visitors but Jupp Heynckes's side started to create chances with Jannik Vestergaard almost gifting the champions an own goal and Kingsley Coman having a low shot saved onto the post by Yann Sommer as it started to become clear it wasn't going to be Bayern's night.
The German champions continued to press and finally got their goal on 73 minutes when Arturo Vidal's low volley was parried over the line by the otherwise impressive Yann Sommer, who in truth should probably have kept it out.
From there Gladbach did their best to frustrate their visitors, and did just that as Bayern were restricted to long range shots and hopeful efforts.
With just three minutes of added time to save a result, Gladbach caught Bayern on the break after the linesman failed to notice substitute Josip Drmic was offside, but the Swiss forward blazed his shot wide.
Bayern then went up the other end and thought they had levelled it when Kwasi Okyere Wriedt's knock-on looked to be rolling in but his effort of sorts was cleared off the line as Gladbach held on to a famous win against an out of sorts Bayern.
It ended a run of nine unbeaten Bundesliga games and leaves the champions just three points clear at the top with their conquerers moving to with in just four points.
What would of worried Heynckes more is the manor of the defeat and the lack of pace and creativity his side showed after multiple injuries to their forward line left him with with a paper thin squad for the game. Even worse, James Rodriguez looks set to join the injury list after he was taken off at half time following a nasty clash of heads with Tony Jantschke in the first half.
Bayern will look to bounce back next Saturday when they host Hannover 96.