BERLIN (AFP) - Bayern coach Ottmar Hitzfeld refused to pull his punches after the Bundesliga leaders suffered the humiliation of losing 2-0 to relegation-threatened Energie Cottbus.

A Bayern side - packed with star strikers Luca Toni and Miroslav Klose, plus midfield generals Bastian Schweinsteiger and Franck Ribery - produced a dreadful first-half performance at the Stadium of Friendship on Saturday.

Prior to kick-off, Cottbus were bottom of the table and their main claim to fame this season had been to have German chancellor Angela Merkel as an honorary fan.

But the home side led 2-0 after the first 45 minutes as Bayern shot themselves in the foot with Ribery missing a 28th minute penalty to sum up their lacklustre performance.

After losing the second-leg of their UEFA Cup last-16 clash at home to Anderlecht last Thursday, this was Bayern's second defeat in three days and Hitzfeld was far from impressed with what he saw.

"It was a black day for us. Right from the start, we shirked our tackles, gave them too much space, and made no end of mistakes in defence," said Hitzfeld on the club's website with his side's lead trimmed to five points following their shock defeat.

"It's highly possible one or two of my players were deceived by all the talk of the title race being over and had started dreaming we'd won the championship already.

"We lacked concentration and thought we could take it easy, just like against Anderlecht, which basically should have been enough of a warning.

"We lost every single challenge in the first ten minutes, and from then on, I knew it was going to be difficult for us."

While Bayern struggled through the first-half, Cottbus striker Branko Jelic struck with well-taken goals to give his side a 2-0 half-time lead and the Munich side never recovered.

Cottbus' win - only their fourth of the season - lifted them out of the relegation zone and increases their chances of avoiding the dreaded drop.

"We didn't show up," admitted Belgian defender Daniel van Buyten.

"We weren't aggressive enough, our passing was pedestrian, and we couldn't find any gaps.

"Cottbus simply sat back and waited to hit us on the break.

"The first half was the worst we've played all season.

"Anyone thinking we've already won the league is making a huge mistake. Everyone wants to beat Bayern, so it's a mistake to go out there thinking: maybe it'll be easy.

"We didn't invest enough in the game.

"Cottbus were much more alert, but we let our heads hang. We didn't do enough to take anything from the game."

Bayern will be desperate to get their league campaign back on track when they face title-rivals Bayer Leverkusen at the Allianz Arena next weekend.