5 things we learned in the Bundesliga this weekend

Five things we learned from the seventeenth round of Bundesliga matches, the first after the winter break.

Ice-cold Lewandowski

Robert Lewandowski's double rescued Bayern Munich in Friday's 2-1 comeback win at Freiburg due to his ice-cold finishing in sub-zero temperatures.

Without his 14 goals and three assists this season, Bayern would be 10 league points worse off, seven behind second-placed RB Leipzig, and coach Carlo Ancelotti admits it was a below-par Bayern performance.

After Freiburg took an early lead, Lewandowski equalised with a superb first-half volley, then hit the 91st-minute winner by chesting down Franck Ribery's cross and firing home off his left foot.

"It most important to win our first game of the year," said Lewandowski.

"It was minus nine (degrees Celsius) and the pitch wasn't perfect, so you just want to take the three points."

Bayern is on course for a fifth straight Bundesliga title, but needs to improve with Arsenal looming in the last 16 of the Champions League.

Hradecky's mad moment

Eintracht Frankfurt goalkeeper Lukas Hradecky says he would do the same thing again despite being sent off just 125 seconds into Saturday's 3-0 defeat at RB Leipzig for handling the ball outside the area.

The game had barely begun when the Finland international was dismissed after dropping onto a loose ball outside his area.

"I had no choice and I'd do the same thing again," he told Sky after the defeat saw Frankfurt drop to sixth.

Despite his lightning red card, Hradecky was spared the unwanted record for the Bundesliga's fastest dismissal.

Lebanon defender Youssef Mohamad was dismissed after 92 seconds into Cologne's opening game of the 2010-11 season in a 3-1 home defeat against for bringing down a player who was through on goal.

Dortmund wins 'ugly'

After finishing 2016 with three draws, Borussia Dortmund won 'ugly' with a 2-1 victory at ten-man Werder Bremen to go fourth, but coach Thomas Tuchel is having to come to terms with shaky defending.

Dortmund, who faces Benfica in the last 16 of the Champions League next month, led through Andre Schurrle early goal and Werder goalkeeper Jaroslav Drobny dismissal on 39 minutes for fouling Marco Reus.

But Bremen's Fin Bartel equalised after the break having run between two defenders before Lukasz Piszczek hit Borussia's winner.

In their previous league game last December, Augsburg midfielder Martin Hinteregger beat five Dortmund defenders to set up the equaliser in a 1-1 draw.

"When will the stability come? Good question," Tuchel told journalists.

"We were sloppy, which annoyed us, but is outweighed by the joy of winning 'ugly'.

"Perhaps we have to accept that we aren't so stable this season and learn to live with that."

Red cards cost Hamburg

Relegation-threatened Hamburg is suffering from a lack of discipline with five sendings-off in their last 11 games.

The latest to see red was Albin Ekdal for a second booking just 33 minutes into Saturday's 1-0 defeat at Wolfsburg.

"That's not on. We need to talk about this. We must finish with 11 men and this can't happen again," fumed coach Markus Gisdol with Hamburg third from bottom.

Having already fouled on Wolfsburg's new signing, France winger Paul-Georges Ntep, Ekdal was sent for an early shower for a crunching tackle, again on Ntep, just five minutes later.

"That was stupid from me and I'm sorry for the team," said the 27-year-old.

Leverkusen breaks penalty curse

Bayer Leverkusen finally broke its penalty curse this season after Hakan Calhanoglu successfully converted a spot kick after his team had failed with its previous five attempts this season.

The Turkish international winger drilled home from the spot on 36 minutes in a 3-1 win over Hertha Berlin on Sunday.

Calhanoglu, who also had a penalty saved in November's 3-2 defeat to RB Leipzig, slotted home after a handball from Berlin defender Marvin Plattenhardt.

"I am very relieved. I could feel a bit of pressure, but I know I can score penalties," said the 22-year-old Calhanoglu.