Bayern Munich's German forward Thomas Mueller (second left) scores the 0-3 goal during the German first division Bundesliga football match Schalke 04 v FC Bayern Munich in Gelsenkirchen, western Germany, on Jan 24, 2021. (LEON KUEGELER / AFP / POOL)

BERLIN - Bayern Munich moved seven points clear atop the Bundesliga standings after Thomas Muller's brace paved the way for their 13th win of the season on Sunday.

Bayern have now opened up a seven-point gap to second-placed RB Leipzig, while Schalke's relegation worries increase

The Bavarians dominated possession in the opening stages and kept Schalke's defense busy, but Leroy Sane and Robert Lewandowski lacked accuracy in front of goal.

Schalke was also dangerous and should have opened the scoring with 11 minutes played, but Mark Uth's header from close range was no problem for Bayern goalkeeper Manuel Neuer.

The opener was scored at the other end after half an hour, as Joshua Kimmich's pinpoint cross into the box allowed Muller to head past Schalke custodian Ralf Fahrmann.

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Despite a powerful performance, Bayern took only a one-goal advantage into the break.

Schalke grabbed a good start into the second half as Matija Nastasic's header forced Neuer to make a diving save in the 52nd minute.

Bayern settled its nerves moments later, as Lewandowski shrugged off Ozan Kabak inside the penalty area before slotting home for a 2-0 lead and his 23rd goal of the season.

The second goal took the wind out of Schalke's sails as Bayern fully controled proceedings. Fahrmann had his hands full but was hapless once again in the 88th minute after Muller nodded home Kimmich's free-kick.

The defending champions were still not done with the scoring, as David Alaba tried his luck with a long-range effort and surprised Fahrmann to round off a 4-0 away win.

Bayern have now opened up a seven-point gap to second-placed RB Leipzig, while Schalke's relegation worries increase as the Royal Blues remain stuck in last place, ten points from safety.

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"I am not entirely satisfied. Sure, we scored four goals, but I also saw that we can do some things better. Sometimes we take too much risk, sometimes we are too slow. There are turnovers we can avoid," Bayern head coach Hansi Flick said.

Elsewhere, Cologne stay in a relegation play-off spot after losing 3-0 to Hoffenheim, who secured all three points on home soil courtesy of Andrej Kramaric's brace.