Bayern knocked Thomas Tuchel's Dortmund off top spot after Pep Guardiola's side romped to a 5-1 win over Wolfsburg on Tuesday, 24 hours before Dortmund dropped their first points of the season with a 1-1 draw at Hoffenheim.
Despite writing Bundesliga history with five goals in nine spectacular minutes against Wolfsburg, Robert Lewandowski is not guaranteed a start at the beginning of a busy week for the Bavarian club.
After Mainz, Bayern host Dinamo Zagreb in the Champions League on Tuesday, then welcome Dortmund to the Allianz Arena on October 4 in a key Bundesliga clash.
Oktoberfest is in full swing in Munich, but Lewandowski says they have more important concerns than the annual visit at the invite of a team sponsor.
“We’ll be at Oktoberfest next week, but we have our next game on Saturday,” said Lewandowski.
“When you play every three days, like we are at the moment, recovery is very important.
“For the moment, I can be pleased, but we’re already focused on the next game and next week we have a very important game in the Champions League.
“We need to stay focused and keep giving it our all.”
Between them Lewandowski and Thomas Muller have scored 14 goals in the six league games so far this season.
Neither are sure to start at Mainz, with Germany’s World Cup winner Mario Gotze also in the mix as Guardiola considers who to rest.
Mainz, who lost 1-0 to Bayer Leverkusen on Wednesday, have won two of their last six games at home to Bayern, the last of which was in 2011.
Dortmund host Darmstadt with Gabon striker Pierre-Emerick Aubameyang having made history by scoring in each of his opening six games so far.
Despite drawing, Dortmund are unbeaten in their first 12 matches in all competitions this season.
Last season’s runners-up Wolfsburg, who now lag seven points behind Bayern after their Munich mauling, are set to be without Luiz Gustavo for Saturday’s visit to bottom side Hannover.
The Brazil midfielder picked up a knee injury and faces a race to be fit in time for Wednesday’s Champions League visit to Manchester United.
Fresh from Wednesday’s 4-2 win against Augsburg, which took them off the bottom of the table, Borussia Monchengladbach travel to Stuttgart looking for their second straight win under caretaker coach Andre Schubert.
Gladbach are looking for Lucien Favre’s replacement and the Stuttgart game is their final warm-up before they host Manchester City in the Champions League next Wednesday.
Fixtures (UAE times)
Cologne v Ingolstadt (5.30pm)
Wolfsburg v Hannover (5.30pm), Stuttgart v Borrusia Monchengladbach (5.30pm), Augsburg v Hoffenheim (5.30pm), Werder Bremen v Bayer Leverkusen (5.30pm), Mainz v Bayern Munich (5.30pm), Hamburg v Schalke (9.30pm)
Eintracht Frankfurt v Hertha Berlin (5.30pm), Borussia Dortmund v Darmstadt (7.30pm)
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