After a less than masterful performance, FC Bayern suffered their fifth defeat of the season in the Bundesliga.

A week after successfully defending their title, the Munich team lost 3-1 (2-1) at FSV Mainz 05 on Saturday.

Jonathan Burkardt (18th minute), Moussa Niakhaté (27th) and Leandro Barreiro (57th) scored in front of 33,305 fans in the sold-out Mainz Arena for the hosts, who played like unleashed and ended their negative series of five games without a win in a spectacular way.

Robert Lewandowski's 34th goal of the season (33rd) was not enough for Bayern, who had changed four positions and offered a disappointing performance.

The record champion never found his game against stormy Mainz.

Burkardt almost put the 05ers in the lead after just 100 seconds, but his shot from an acute angle jumped back into the field from the underside of the bar.

Munich keeper Sven Ulreich, who surprisingly replaced national goalkeeper Manuel Neuer, would have had no chance.

Shortly thereafter there was renewed excitement in the Munich penalty area when Burkardt was brought down by Benjamin Pavard and Mainz demanded a penalty.

But referee Sascha Stegemann's whistle remained silent.

The guests seemed strangely lethargic and were promptly punished for it.

Shortly after Alexander Hack failed at Ulreich from close range, Burkardt overcame the Bayern goalkeeper with a low shot to give Mainz the acclaimed lead.

And things got even worse for Bayern, who were missing Dayot Upamecano, Kingsley Coman and the ailing Thomas Müller.

After a free-kick cross from Aaron, Niakhaté was completely free at the far post and steered the ball over the line to make it 2-0 for Rheinhessen.

On the other hand, there was hardly anything to be seen from the Munich team.

Against the aggressive home side, the record champions could hardly put themselves in the limelight.

So once again world footballer Lewandowski had to judge with his individual class.

The striker scored the connection with a skillful turning shot.

Eric-Maxim Choupo-Moting had just hit the outside of the post with a header.

Bayern coach Julian Nagelsmann reacted to his team's poor performance during the break and brought on Leroy Sané and Jamal Musiala to start again.

The guests now acted a little more purposefully, but were countered.

Barreiro restored the old two-goal gap with an untenable deflected shot by Pavard.

After that, Mainz remained the better team.

Karim Onisiwo (71st) missed the fourth goal by just a few centimeters with a shot across the crossbar.

Bayern pressed again at the end, but couldn't turn the game around.