Bayern Munich returned from the two-week Christmas break looking rusty before fighting back from two goals down to beat second-from-bottom Mainz 5-2 in a rip-roaring Bundesliga contest on Sunday. They now sit at the top of the league with 33 points from 14 games, two more than second-placed RB Leipzig who won 1-0 at VfB Stuttgart on Saturday.

Bayern midfielder Joshua Kimmich, who sparked the home side's comeback with their first goal, conceded that his side had been below par in the first half when they missed a string of chances.

"We came out in the second half with a completely different attitude but we were still fortunate that Mainz didn't score a third goal," he told Germany's Sky television.

The German title holders were trailing 2-0 at halftime before they woke up with their run of goals, including a brace by Robert Lewandowski which took his tally to 22 goals in all competitions.

Jonathan Burkardt fired Mainz ahead against the run of play in the 32nd minute with a superb finish from 15 meters after shaking off Jerome Boateng. Alexander Hack made it 2-0 12 minutes later with a thumping header from Daniel Brosinski's cross.

Kimmich pulled one back in the 50th minute with a close-range header after Lewandowski nodded a Serge Gnabry cross into his path, before Leroy Sane equalized five minutes later with a scorcher from 20 meters into the bottom right corner.

Halftime substitute Niklas Suele turned the tide when he volleyed home from inside the area through a forest of bodies before Lewandowski forced Mainz into submission.

Lewandowski converted a penalty after Leandro Barreiro had brought down Gnabry with a late tackle and then bundled in a Thomas Mueller cross as Mainz collapsed in the final 20 minutes.

(With input from Reuters)