Hamburg upset Dortmund

Dortmund coach Jürgen Klopp decided to rest midfielder Ilkay Gündogan, meaning that prodigal son Nuri Sahin got his first start since returning to the defending champs on loan during the winter break.

In front of a home crowd, Sahin and his teammates got off to a fortunate beginning. Hamburg defender Heiko Westermann and keeper Rene Adler couldn't agree who would chase down a long ball, and striker Robert Lewandowski nutmegged Adler to grab Dortmund the lead.

A lead that only lasted a minute. Artjoms Rudnevs was left criminally along in the middle of Dortmund's area, and he equalized. Roughly ten minutes later, Heung-Min Son went on a mazy run and rifled home to put the visitors ahead. It was an effortless-looking goal that probably increased the number of international suitors for the South Korean striker.

Hamburg were playing a very physical game, and that may have gotten under the defending champs' skin. At the half hour mark, Lewandowski saw a straight red card for kicking Per Skjelbred. It was hard to tell whether it was a frustration foul by the Polish striker or whether he simply didn't see his opponent. In any case, it didn't help Dortmund's cause.

"You could do without days like these," Klopp told reporters after the game. "But if you're a football player for a length of time, you're going to have a few crappy days."

On the hour mark, the hosts probably thought they still had a chance. Hamburg's Jeffrey Bruma also got his marching orders for a professional foul on Marko Reus. But Dortmund's hopes were crushed immediately when Rudnevs struck to make it 3-1 for Hamburg. It was a fine day for the Latvian striker.

And not to be outdone, Son also notched his brace and completed the 4-1 scoreline in the dying minutes. Dortmund's back line, without the injured Marcel Schmelzer, was a true shambles – a worrying sign ahead of their Champions League clash with Schakhtar Donetsk on Wednesday.

Foals get late equalizer

For a time it looked as though Leverkusen would take advantage of the door Dortmund opened and reclaim second place in the table. Perhaps they were overconfident in Mönchengladbach since the hosts hadn't beaten them there for more than twenty years – back when computers still needed floppy-disks.

Leverkusen dominated the first half, but it was Gladbach taking the lead just before the break, when Martin Stranzl headed in the Foals' first shot on goal.

Five minutes after the restart, Sidney Sam levelled the score with a curling shot from just outside the area.

The see-saw continued in minute 58. Gladbach went back in front, when a Juan Arango cross found an unmarked Luuk de Jong. But a mere 73 seconds later Stefan Kiessling tapped in at the other end.

And in minute 61, André Schürrle pushed the ball forward, collected a pass and beat keeper Marc-Andrè ter Stegen from close range. Leverkusen were up 3-2 and looked as though they would lock down that scoreline.

But five minutes from time, Gladbach were able to penetrate, and Patrick Herrmann headed home an equalizer. The match ended 3-3 and left Leverkusen, who stay in third place, one point behind Dortmund, ruing their late lapse in defensive intensity.

"We dominated as though we were the home town," Leverkusen coach Sascha Lewandowski said after the match. "But the way we defending in the air was really weak. We need to be calmer and more efficient."

Nor could Frankfurt take full advantage of the defending champs' collapse. This year's pleasant surprises played a dull scoreless draw at home against Nuremberg.

Bayern extend league lead

Those three results meant that Bayern Munich had the chance to put even more distance between themselves and the pack against Schalke in Saturday’s late match. With a Champions League match against Arsenal in the offing, Bayern coach Jupp Heynckes chose to rest Thomas Müller and Mario Mandzukic in favor of convalescents Arjen Robben and Mario Gomez.

Meanwhile, Schalke had to compensate for a raft of injuries. Striker Klaas-Jan Huntelaar, for example, was out with an eye condition, leaving Finland’s Teemu Pukki to start up front.

And it only took Bayern 18 minutes to seize the initiative. Franck Ribery made Marco Höger look as though he was rooted to the ground and drew a penalty. Youngster David Alaba did the honors, cool as a cucumber, to get the hosts going. And on the half hour mark, Sebastian Schweinsteiger drilled in a free kick to double the hosts’ advantage at the break.

The outcome was more or less decided at that point, and attention shifted to whether Robben and Gomez could build some confidence. Gomez got an assist as Alaba sealed a brace in minute 51. And the forward scored one himself in minute 63, with Robben getting the assist.

The win means Bayern are now a massive 15 points ahead of Dortmund with 13 rounds to play. They were also able to give some of their key players some regeneration time ahead of their Champions League campaign resuming against Arsenal on February 19.

Schalke have earned only six points from their previous nine league matches, and fan dissatisfaction with sports director Horst Heldt and coach Jens Keller looks certain to intensify.

"That didn't even come close to living up to our expectations," disgusted Schalke defender Benedikt Höwedes huffed after the match.

Bremen destroy Stuttgart

Earlier, Stuttgart were hoping to break a four-game losing streak when they welcomed Werder Bremen to town. But Bremen were impolite guests, subjecting their hosts to a 4-1 thrashing.

Werder were the better team from the get-go, and after a little over half an hour, Mehmet Ekici converted a Kevin de Bruyne cross.

Just after the restart, Ibrahima Traore equalized for Stuttgart with a skillful left-footed scissor kick. But a blackout by defensive midfielder William Kvist killed off the hosts' momentum. Aaron Hunt swooped in to restore Bremen's lead.

Ekici, who is finally living up to his potential, blasted in a beauty of a free kick, and De Bruyne finished Stuttgart off with a nifty late lob. Stuttgart remain the only Bundesliga team without a point in 2013 and desperately need a result to stop their plunge toward the relegation zone.

Last-placed Greuther Fürth won't pose much of a threat to Stuttgart. They went down meekly to Wolfsburg 1-0. Bas Dost was the goalscorer for the Wolves. Fürth has still yet to win a home match this season.

In Hanover, the hosts only needed a Mame Diouf goal in minute 8 to emerge as 1-0 winners against Hoffenheim. New Hoffenheim keeper Heurelho Gomes, who replaced former German national Tim Wiese, didn't look particularly impressive as the striker nodded home from around three inches.

On Sunday, Augsburg continue their relegation fight against Mainz, and Freiburg face Düsseldorf.