BERLIN (AFP) - Coach Ottmar Hitzfeld rued a "black day" for Bayern Munich and admitted his side's complacent streak had been exposed as the league leaders were humbled at struggling Energie Cottbus on Saturday.

Serbian striker Branko Jelic struck twice for the home side as Cottbus - bottom of the league going into the tie - pulled off the Bundesliga's shock of the season.

Jelic, a winter signing from Chinese outfit Xiamen Lanshi, took both goals well while Bayern failed to assert their authority with top stars Bastian Schweinsteiger, Luca Toni and Franck Ribery in the side.

Cottbus picked up only their fourth win of the season as mighty Bayern suffered their second defeat in three days following their 2-1 UEFA Cup humbling by Anderlecht last Thursday.

Lacklustre leaders Bayern were left red-faced when Cottbus took a shock lead as Jelic drilled home his shot on 18 minutes before Bayern's French star Ribery had a 28th minute penalty saved at the Stadium of Friendship.

And the home side extended their lead just seven minutes before the half-time break when Jelic struck again to leave Bayern reeling and give Bayern an almighty wake-up call after dominating the league so far this season.

"That was a black day for my team, it is possible that players had believed the championship was a walk in the park," said Hitzfeld whose side's seven point lead has been trimmed back to five points.

"The victory was deserved by Cottbus. They played with a large heart, as you have to do if you are involved in a relegation battle. I am disappointed, particularly in the way we were beaten.

"We were asleep for the first 20 minutes and didn't win our battles. Nearly everything went wrong."

And Cottbus coach Bojan Prasnikar - who was true to his pre-match assertion Energie would attack their illustrious hosts - was delighted as his side moved out of the bottom three.

"We were under intense pressure," said Prasnikar. "But this win will give us a great deal of confidence. We made few errors and played with big hearts.

"The first goal was a set move by us and we stayed tight at the back after we went ahead and made few mistakes in midfield."

The result leaves UEFA Cup quarter-finalists Bayern to dwell on only their second league defeat of the season while Cottbus lifted themselves out of the bottom three into 15th.

Hamburg moved up to second in the table, knocking Werder Bremen down into third, with a 1-0 win at Borussia Dortmund thanks to a second-half strike by Peru forward Jose Paolo Guerrero.

Bremen have the chance to reclaim second spot when they face VfL Wolfsburg on Sunday, the same day fourth-placed Bayer Leverkusen are at home to Nuremberg.

There was a battle royal at Hanover as the home side fell behind to Arminia Bielefeld defender Andre Mijatovic's strike on 14 minutes, but equalised two minutes later through Netherlands midfielder Arnold Jan Bruggink.

But a header by striker Christian Eigler on 38 minutes put relegation-threatened Bielefeld, who drop into the bottom three, ahead before Czech striker Jiri Stajner equalised for Hanover on 56 minutes to make it 2-2.

After their 6-3 home win over Werder Bremen last weekend and their 1-0 win at Energie Cottbus on Tuesday, VfB Stuttgart had a 1-1 draw at strugglers VfL Bochum to stay sixth in the league.

Midfielder Christoph Dabrowski put the home side ahead on 20 minutes before Germany international Thomas Hitzlsperger levelled two minutes after the break.

Eintracht Frankfurt picked up their seventh win of the year to go seventh when midfielder Michael Fink sealed their 1-0 win at Karlsruhe with a first-half strike.

In the day's other result Hansa Rostock moved four points clear of the relegation zone as they were held 0-0 at home by Hertha Berlin.

On Friday night, Schalke 04 - who drew Barcelona in the Champions League quarter-finals - consolidated their place in the top five with a 2-1 win over Duisburg.

Germany defender Heiko Westermann hitting the winner on 74 minutes and the defeat means Duisburg are now bottom of the table.