BERLIN (AFP) - Bayern Munich suffered their fifth loss in six games on Saturday as their former striker Nils Petersen scored an 89th-minute winner for relegation-threatened Freiburg to claim a shock 2-1 victory.
Having been knocked out of the Champions League's semi-finals by Barcelona 5-3 on aggregate, despite a 3-2 home win against Barca on Tuesday, Bayern's bad week continued.
The loss at Freiburg followed their cup defeat at Dortmund and league losses against Leverkusen and Augsburg, plus the away defeat at Barca in Bayern's nightmare three-week period since winning their 25th German league title.
Bayern took an early lead in Freiburg when right winger Mitchell Weiser's cross was hammered home by Germany captain Bastian Schweinsteiger, who was making his 500th Bundesliga apparence, with 11 minutes gone.
But to the delight of the Freiburg crowd, the hosts drew level thanks to a superb goal when midfielder Admir Mehmedi hit the bottom left-hand corner on 33 minutes.
Freiburg were unlucky not to be awarded a penalty after Bayern defender Rafinha fouled Mehmedi in the area early in the second half, while Schweinsteiger hit the crossbar with a free-kick with 20 minutes left.
But ex-Bayern striker Petersen hit the winner just three minutes after coming off the bench to give Freiburg their first win over his former employers in 19 years when he converted Karim Guede's pin-point accurate cross on 89 minutes.
The result lifted Freiburg out of the relegation places up to 14th, but with one match left things remain tight at the bottom with just four points separating bottom six sides of Paderborn, Hamburg, Stuttgart, Hanover, Freiburg and Hertha Berlin.
Hamburg dropped back to 17th with a 2-1 defeat at VfB Stuttgart who climbed off the bottom to 16th as Hamburg's midfielder Gojko Kacar scored his third goal in three games with an early header, but Stuttgart roared as Christian Gentner and Martin Harnik netted first-half goals.
Paderborn defender Uwe Huenemeier suffered the nightmare of heading into his own net to seal his side's 1-0 defeat at Schalke which put them bottom of the table.
Ten-man Hanover 96 boosted their survival chances with a first win since December with a 2-1 victory at Augsburg, captain Lars Stindl scoring twice to hoist his team up to 15th on 34 points.
Hertha Berlin have 35 points after being held to a goalless draw at home to Eintracht Frankfurt, and are hovering just above the bottom three.
Third-placed Borussia Moenchengladbach's 2-0 win at Werder Bremen confirmed Lucien Favre's side direct qualification into the Champions League thanks to Raffael's second-half goals.
Bayer Leverkusen will finish fourth, and go into the qualifier for a place in the Champions League's group-stage, after their 2-0 home win against Hoffenheim as free-kick specialist Hakan Calhanoglu curled one in just before the half-time whistle before Stefan Kiessling added Bayer's second.
Wolfsburg enjoyed a 2-1 win at home to Borussia Dortmund in the German Cup final dress rehearsal.
Wolves' took the lead on 41 seconds when midfielder Daniel Caligiuri tapped home, but Borussia drew level when Kevin Kampl was fouled in the area by home goalkeeper Diego Benaglio and Pierre-Emerick Aubameyang converted the resulting penalty with 11 minutes gone.
The hosts restored their lead when Brazil defender Naldo took a speculative swing at a Ivan Perisic header and the shot beat Dortmund goalkeeper Mitchell Langerak four minutes into the second half for the winning goal.
The two sides will meet again at Berlin's Olympic Stadium on May 30 in the cup final.