Conor McGregor would kick Floyd Mayweather's ass in the boxing ring ... that's according to UFC champ Joanna Jedrzejczyk, who says she's so sure of McGregor, SHE'D BET MONEY ON IT.
Joanna is a UFC stud herself ... 14-0 and the reigning strawweight women's champion ... we got her in L.A. and wanted to know if she thought McGregor had a chance against Floyd.
She DEFINITELY does ... saying if it was about putting cold hard cash where her mouth is, she wouldn't hesitate to do it.