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.
After coming on in the win over Schalke, Philippe Coutinho and Ivan Perisic were handed their full Bayern Munich debuts against Mainz.
Robert Lewandowski has started the new season in impressive form and Bayern Munich boss Niko Kovac wants a new contract to be sorted.
Bayern Munich brought in Philippe Coutinho on loan from Barcelona last week and he has quickly won over new team-mate Robert Lewandowski.
Robert Lewandowski is even more impressive in person than on TV, Philippe Coutinho said after his Bayern Munich debut.
Bayern Munich recovered from a disappointing 2-2 draw in their season opener as they beat Schalke 3-0 in Gelsenkirchen.
Juventus forward Cristiano Ronaldo "does not agree" with the money being spent on young players in the modern game.
Philippe Coutinho joined Bayern Munich on loan from Barcelona and Jurgen Klopp said Liverpool could not afford the playmaker.
Philippe Coutinho will look to continue a proud legacy of Brazilians at Bayern Munich after joining the Bundesliga club on loan.
Philippe Coutinho will wear the No.10 jersey vacated by Arjen Robben at Bayern Munich after the Dutchman gave the club his blessing.