Heynckes praise for Martinez

Bayern appeared to be cruising to victory at 2-0 up but, when it conceded a penalty, it looked at risk of caving in until its 40 million euros ($49.76 million) man came on to the field for only his second appearance for the club.

"Above all, it was the introduction of Javi Martinez which led to us playing with more control again," said Heynckes.

"He played very well going forwards and very intelligently. And then he created the third goal sensationally."

Bayern was perhaps thinking ahead to Wednesday evening's (Thursday morning AEST) UEFA Champions League tie with Valencia when it appeared to sit back after going two goals up inside the first 13 minutes.

"Conceding the goal was unnecessary," said captain Philipp Lahm.

"There was a phase in which we just lost control of the game a little, but otherwise we can be very happy.

"The first half was very, very good - we should have made it 3-0 earlier on."

Mainz arrived in Munich with a good record against Bayern with a win and a draw on its last two visits to the Allianz Arena, but the early goals saw its gameplan go out of the window.

"We were behind incredibly quickly, and unfortunately, and that was pretty much game over," said coach Thomas Tuchel.

"We showed a bit more courage after half-time. On the one hand I am angry, but on the other hand it is the most normal result when Mainz play Bayern."