Bayern Munich came looking for a title party and were served with a cold dose of reality as survival scrappers Mainz earned a stunning 2-1 win over the Bundesliga leaders.

First-half goals from Jonathan Burkardt and Robin Quaison put in-form Mainz in charge, and a leggy Bayern side - who would have been crowned champions with a victory - lacked the zip in their game to overturn that deficit.

Manuel Neuer was at fault for the opener, but also produced some big saves to keep Bayern in touch with their impressive hosts, who have been the most-improved team in the league in the second half of the season.

When Quaison headed the second, he showed the aerial threat that was rarely seen from Bayern's fit-again talisman Robert Lewandowski in this game. Lewandowski snatched a last-gasp consolation after a defensive clanger, but it came too late to be significant.

Burkardt stunned Bayern in the third minute when he was left unattended on the edge of the penalty area and fired a thumping shot that Neuer could only help into the left corner.

Bayern had Lewandowski back in their ranks after a knee injury absence, but before the Polish striker could show any threat they were almost two goals behind, Neuer producing a fine save at full stretch to touch a 20-yard header from Danny Latza against the left post.

Lewandowski fired waywardly from his first chance before Neuer again prevented Bayern slipping two goals behind, Quaison turning Jerome Boateng far too easily and hitting the target with a thumping shot that bounced away off the well-placed goalkeeper.

Bo Svensson's Mainz side, having won four and drawn two of their previous six games to surge out of the relegation zone, doubled their lead in the 37th minute when Quaison headed past Neuer after Philipp Mwene's free-kick from the left proved a perfect, teasing delivery.

Hansi Flick's reaction was to bring on three substitutes at the start of the second half, hauling off Leon Goretzka, who was perhaps fortunate to avoid a first-half red card, plus Kingsley Coman and Leroy Sane, and introducing Eric Maxim Choupo-Moting, Jamal Musiala and Tanguy Nianzou.

A stray arm from Lewandowski caught Mainz midfielder Leandro Barreiro in the face, drawing blood, but it appeared accidental. It was nevertheless not the impact Bayern were looking for from their star striker.

Bayern trailed 2-0 in the first meeting of these sides this season but recovered to win 5-2; however, until Lewandowski's stoppage-time strike, their second-half goal threat in this game was limited to half-chances that the likes of Choupo-Moting and Joshua Kimmich could not convert.

Hertha Berlin have requested three matches be postponed due to being forced into 14-day quarantine as a result of COVID-19 cases within the Bundesliga club.

Hertha have asked to delay scheduled fixtures against Mainz (April 18), Frieburg (April 21) and Schalke (April 24) after left-back Marvin Plattenhardt tested positive for coronavirus on Thursday. 

Head coach Pal Dardai, assistant coach Admir Hamzagic and striker Dodi Lukebakio had positive tests earlier in the day, prompting the German club to implement the two-week quarantine. 

Hertha initially had planned to play their matches during that period but the additional positive test to Plattenhardt prompted the plea to push them back.

"Due to the cases that have occurred, we are now forced to a 14-day quarantine at home," said sporting director Arne Friedrich, who took charge of training on Thursday with Dardai out.

"From a health point of view, this is absolutely the right step. because we now have to play six Bundesliga games by the end of the season on May 22, 2021 in the fight to stay relegated in May. 

"During the quarantine at home, the team will keep fit with virtual training units under the guidance of the coaching team. 

"We accept the situation despite the difficult circumstances and will throw everything in our power for a successful season finale into the balance."

There was no immediate response from the German Football League (DFL), which had announced new dates for several 2.Bundesliga matches that had been postponed due to coronavirus cases. 

Hertha sit just outside the relegation play-off place on goal difference ahead of fellow strugglers Arminia Bielefeld, while the capital club are three points clear of the automatic relegation positions with six games remaining.

Bayern Munich came from behind for an eighth successive Bundesliga match as the champions overcame struggling Mainz 5-2 at Allianz Arena.

Hansi Flick's side have not taken the lead in a league game since October and might have been staring down the barrel of a second defeat of the season had Danny Latza beaten Manuel Neuer early in the second half.

Mainz had a 2-0 lead at that stage, with Jonathan Burkardt and Alexander Hack scoring in the first half, but Joshua Kimmich and Leroy Sane restored parity in the space of five minutes.

Robin Quaison struck the woodwork as 17th-placed Mainz fought back, though Bayern ultimately had too much.

Niklas Sule's deflected strike and Robert Lewandowski's double – the first of which came from the spot – settling a thrilling contest firmly in Bayern's favour.