Speculation regarding a summer exit for the Croatia international has been building steadily for some months now.
From the moment that it was announced that Robert Lewandowski will be joining Bayern this summer as a free agent - once his contract at Borussia Dortmund has expired - doubts have been cast over Mandzukic's role.
The rumours have intensified after it was revealed that Pep Guardiola had left the striker out of his squad for the German Cup final.
Disciplinary reasons have been cited for his absence, and they could force him a little closer to the exit door.
Were Mandzukic to be made available, there would be no shortage of takers for a man who has been a regular source of goals for Wolfsburg and Bayern in the Bundesliga and one who has netted 13 times in 48 appearances for his country.
"If Mario stays here, it won't be easy for him because a world-class player is coming to us," Rummenigge told FAZ.
"The question is whether he wants to face up to his competition or would prefer to go to another club.
"We are open and fair and we talk about everything, so nothing is decided."