Five things we learned from the Bundesliga this weekend

Thomas Mueller finds Bayern Munich's form 'sobering', Borussia Dortmund are the next hurdle facing RB Leipzig and Torsten Frings is fuming in Darmstadt. Here are five things we learned from the 18th round of matches in the Bundesliga:

Five things we learned from the Bundesliga this weekend

Bayern-Arsenal live

'Sobering' Bayern win 

Even Bayern Munich's chief prankster Thomas Mueller admits the league leaders' form is no laughing matter after describing Saturday's narrow win at Werder Bremen as 'sobering'. Bayern have posted lacklustre 2-1 wins at both Freiburg and Bremen in their opening league games of 2017. "Apart from the result, we can't really be satisfied," said Mueller.

Arjen Robben and David Alaba put Bayern 2-0 up before Max Kruse netted for relegation-threatened Bremen, who are 15th, but pushed Munich until the final whistle.

"Not much is really working at the moment and we're finding few combinations. It doesn't feel brilliant on the pitch," said Mueller, who scored 20 league goals last season, but has managed just one this term.

Bremen keep hold of Gnabry...for now 

Despite interest from Bayern Munich, struggling Bremen are set to keep Germany winger Serge Gnabry for the foreseeable future, according to his father. "Serge has to do something here before he takes the next step. My son sees it the same way," Gnabry's dad Jean-Hermann told Bild. The 21-year-old left Arsenal for Werder last August after signing a deal until June 2020.

He has been linked to Bayern since scoring a hat-trick on his Germany debut against minnows San Marino in November. Gnabry reportedly has a release clause for 10 million euros ($10.6m), but his father wants him to stay. "(Brazil midfielder) Diego was here for three years, Mesut Ozil played here for three years. Why should Serge not stay here for three years?" he added.

Serge Gnabry of Bremen

Dortmund miss chance to go 3rd 

Fourth-placed Borussia Dortmund missed the chance to go third on Sunday as they leaked a late goal in their 1-1 draw at Mainz -- the fourth time they had to settle for a point in five league games. Marco Reus put last season's runners-up ahead after just three minutes, but shaky defending let Danny Latza head Mainz level seven minutes from time.

"If you don't want to defend consistently, then something like that can happen," fumed Dortmund's frustrated captain Marcel Schmelzer. "We thought we were a step further on, so it is bitter to have let a win slip out of our hands." Dortmund face second-placed RB Leipzig on Saturday with the chance to avenge their 1-0 away defeat in September and close the 14-point gap behind leaders Bayern.

Darmstadt down in the dumps 

Ex-Germany midfielder and new Darmstadt coach Torsten Frings was fuming after the bottom club's 6-1 thrashing at home to Cologne. "I dreamt that we'd win the game -- what am I supposed to do now?" the 40-year-old asked following the second heaviest league defeat in the club's history.

Frings directed his anger at want-away defender Florian Jungwirth, who he had thrown out of the match day squad. "He's been training all week as if he wants to move to the USA," fumed Frings. "When someone is not prepared to give their all for Darmstadt, he's not in the squad and he can sit in the stands for the next six months."

Frings, who was appointed in December, has a tough task. Darmstadt are seven points from safety, but play neighbours Eintracht Frankfurt in a derby on Sunday.

Leipzig keep title race alive 

RB Leipzig's 2-1 comeback home win against ten-man Hoffenheim was crucial to keep the title race alive. Due to Bayern's 2-1 win at Werder Bremen, defeat to Hoffenheim would have left RB six points adrift in second, until goals by Timo Werner and Marcel Sabitzer sealed the win to keep Leipzig just three points behind.

"That was a 'big point'. We have taken a big step against a direct rival," said Leipzig coach Ralph Hasenhuettl.

Hoffenheim's defeat meant they were the last team in a top European league to lose their unbeaten record this season. This was a second win in Leipzig's tricky first three games of 2017 after last Saturday's 3-0 victory over Eintracht Frankfurt with an away trip to Dortmund to come this Saturday.