Ronda Rousey and Floyd Mayweather have been dogging at each other like a pair of school yard heavies. It may seem odd that Mayweather, undefeated champ that he is, would exchange trash talk with Ronda Rousey. Yet there it is, all in public for the world to see.

Last year, Mayweather said of Rousey, “I don’t even know who she is.”

Then Ronda Rousey beat him as Best Fighter at ESPY Awards.

“I wonder how Floyd feels being beat by a woman for once. I’d like to see him pretend to not know who I am now,” Rousey then commented.

More recently, Mayweather talked smack about how much more money he makes than Rousey.

Daaaaaamn! #MoneyMayweather got told. #RhondaRousey pic.twitter.com/TLZeuKU58u

— J.Michael Trautmann (@JMACdaKID) August 27, 2015

“I’ve yet to see any MMA fighter, or other boxer, make over $300 million in 36 minutes. When she can do that, then call me,” Mayweather taunted.

Rousey shot back, digging at Mayweather over the math of his claim, given how quickly her own fights get finished. Ronda Rousey knocked down her challenger, Bethe Correia, in just 34 seconds when she last defended her Banatamweight title.

“[Floyd] said ‘You make $300 million a night, then you can give me a call’ … and I actually did the math, and given the numbers of my last fight, I’m actually the highest-paid UFC fighter and I’m a woman.”

The female fighter continued, “I think I actually make 2-3 times more than he does per second … so when he learns to read and write, he can text me.” She added, “I’m just more efficient.”

Floyd Mayweather answered that the efficiency doesn’t matter. He simply makes loads more money.

“Big bank take little bank. Let’s play and see how much money you got,” he said. “Last time I checked I was #1 on Forbes. She will never be at my status. Keep trying to get publicity.”

I'm starting to think that Rhonda Rousey wants the D. pic.twitter.com/ZFEhT2N9Fw

— Nathan Slaven (@Slaven_24) August 26, 2015

The fight between Floyd Mayweather and Manny Pacquiao was so highly-anticipated for so long that it was almost anti-climactic when Mayweather beat Pacquiao. Now the stir is about whether or not Ronda Rousey might be able to beat Mayweather.

And some MMA trainers say their money is on the lady.

Brian Michelino, a MMA coach in New York, argues that the kicking and grappling elements of MMA would be the defeat of Mayweather.

“In an MMA fight I’m pretty confident that she would mess him up, especially since Floyd Mayweather does not have grappling experience,” Michelino said.

UFC president Dana White said simply, “Ronda would rag doll him.”

Could female UFC champion Ronda Rousey beat Floyd Mayweather? http://t.co/kO7kzkUUb5 pic.twitter.com/b454JmR7iE

— Business Insider (@businessinsider) August 29, 2015