The richest man in the ring tonight isn't Anthony Mundine or Danny Green

Australian boxers Danny Green and Anthony Mundine face off during the official weigh in ahead of their Friday night bout. Photo / Getty Images.

Both Anthony Mundine and Danny Green are worth millions, but it's nothing compared to the fortune accrued by the man who will share the Adelaide Oval stage with them tonight - ring announcer extraordinaire Michael Buffer.

For those unfamiliar with the name, he's the dashing announcer who stands centre ring before almost every major boxing event and utters the words: "Let's get ready to Rumble."

Those five words have made him famous and also incredibly rich. Forbes estimates his fortune at a $164 million. Buffer can command as much as $65,000 per event to utter the phrase.

In fact every time the words are spoken, even if not by Buffer, he earns money from it. Buffer has a trademark on the phrase - which it turns out was all the idea of his manager, brother and UFC Octagon announcer Bruce Buffer.

Bruce was recently a guest on The Pony Hour podcast with comedian Tony Hinchcliffe and detailed the staggering fortune they've both made off the famous words.

"He (Michael) didn't so much as make a T-shirt off it," Bruce explained. "I said 'what are you doing, you need to do something'.

"I trademarked the phrase, I made toys, I made the three Ready to Rumble boxing video games and the dream came true. We sold over ($522 million) in retail sales in products and ventures."

The two brothers did not grow up together. They share a father but didn't meet until Bruce was 30 years old and a successful businessman, who then sold his companies to link with Michael.