Mueller struck within 12 minutes of his half-time introduction before Lewandowski doubled the lead and Sebastian Rudy added a third after coach Jupp Heynckes started a weakened team.

With one eye on Wednesday's blockbuster Champions League semi-final first leg at home to Real, Heynckes left out several regulars while handing 18-year-old centre-back Lars Lukas Mai his Bundesliga debut.

Arjen Robben captained the side with Thiago Alcantara, James Rodriguez and Jerome Boateng the only other outfield players in Saturday's line-up likely to start against Real.

Both sides had their chances in a goalless first half before Bayern pulled away after Mueller replaced Robben, the Germany international striking on 57 minutes when his first-time shot from a Juan Bernat cross deflected off Salif Sane and past goalkeeper Philipp Tschauner.

Bayern's top scorer Lewandowski added a second just six minutes after coming on himself.

Rudy swung in a corner and the Polish forward headed home to score for the 38th time this season in all competitions.

Defensive midfielder Rudy capped the win a minute from time to leave Bayern 23 points clear of second-placed Schalke, who are at bottom side Cologne on Sunday.

Ten-man RB Leipzig crashed to a 5-2 home defeat by Hoffenheim in a key clash for the Champions League places next season.

Swedish international Emil Forsberg was sent off for a foul on Florian Grillitsch just after the break with Hoffenheim already 3-0 up.

Mark Uth, Serge Gnabry and Pavel Kaderabek all scored as Leipzig's defence buckled in the opening 45 minutes.

Naby Keita pulled a goal back before the hour mark, but Uth scored his second goal with a header before midfielder Lukas Rupp hit Hoffenheim's fifth.

England Under-21 international Ademola Lookman, on loan from Everton, set up Dayot Upamecano to score Leipzig's second on 88 minutes.

The result leaves Hoffenheim fifth, just two points from the Champions League places, while six-placed Leipzig are four adrift.

Mid-table Hertha Berlin romped to a 3-0 win at German Cup finalists Eintracht Frankfurt as Davie Selke, Mathew Leckie and Alexander Esswein scored.

Club captain Christian Gentner and Berkay Ozcan scored Stuttgart's goals in their 2-0 victory over Werder Bremen.

Ex-Tottenham Hotspur midfielder Lewis Holtby boosted Hamburg's hopes of avoiding relegation with their 1-0 win at home to Freiburg.

Holtby jinked through the Freiburg defence and tapped home just after the break to leave second-from-bottom Hamburg five points from safety with three games left.

Hamburg are the only current Bundesliga to have played in every season since its foundation in 1963.

A. Esswein

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