Although Mainz took the lead Bayern Munich came back to win easily, not that head coach Niko Kovac was entirely satisfied by a 6-1 victory.
Bayern Munich claimed their first home win of the season as they came from behind to cruise to a 6-1 Bundesliga victory over Mainz.
After coming on in the win over Schalke, Philippe Coutinho and Ivan Perisic were handed their full Bayern Munich debuts against Mainz.
Everton sold Idrissa Gueye to Paris Saint-Germain on Tuesday, and have moved swiftly to bring in Jean-Philippe Gbamin from Mainz.
Bayern Munich welcome Hertha Berlin for the opening fixture of the 2019-20 season, while newcomers Union Berlin tackle RB Leipzig.
David Martin will step up from playing for Millwall in the Championship after West Ham came calling.
Rene Adler says he can no longer trust his body and will bring an end to his playing days after this season.
Jadon Sancho scored twice as Borussia Dortmund bounced back from their 5-0 defeat to Bayern Munich with a slender win over Mainz.
James Rodriguez's future at Bayern Munich seems in doubt, but the Colombia star wants to make his switch from Real Madrid permanent.
Mainz lost 6-0 to Bayern Munich in the Bundesliga on Sunday, but took the embarrassing defeat in their stride on social media.