The two Bundesliga clubs have been locked in a war of words over the Bavarians' alleged interest in Marco Reus, but the former West Germany international finds it all very funnyBayern Munich and Borussia Dortmund makes him smile.
Already unhappy at having seen Mario Gotze and Robert Lewandowski swap Signal Iduna Park for the Allianz Arena over the past 12 months, BVB are now furious that their Bundesliga rivals appear to be publicly courting star forward Marco Reus.
However, Rummenigge, who caused no end of controversy by speaking about the Germany international's buy-out clause, says that he finds the war of words both amusing and entertaining, citing the hype which surrounded last week's DFL-Supercup showdown between the two sides as a case in point.
“I just have to smile," Rummenigge said of his rivalry with Dortmund counterpart Hans-Joachim Watzke in an interview with Munchner Merkur.
"Honestly, I for one think the slugfest is amusing; I'm not at all annoyed. I always smile when I read something new, because nothing annoys me.
"You have to admit it: Without the taunting in advance, the Supercup would have been rather boring.
"We're all grown up and, in my eyes, [the taunting] is pretty good."
Dortmund are again expected to be Bayern's closest challengers in this season's Bundesliga, which kicks off on Friday night.