According to Arum, Mayweather turned down the career-best purse to meet Margarito on Aug. 12 on HBO Pay-Per-View, instead opting for free agency by buying Arum out of their deal for $750,000.
"I did hear from him," Arum said of Mayweather. "He decided not to fight this summer. I made him a tremendous offer. I think Margarito is the riskiest fight for him of anyone out there."
Mayweather adviser Leonard Ellerbe told ESPN.com that Mayweather passed on the fight not because he is ducking Margarito, but because he couldn't be ready to fight by Aug. 12. Mayweather injured his right hand during a dominating April 8 victory against Zab Judah.
"Floyd is not 100 percent healthy," Ellerbe said. "He has a bruised right hand. His hand is not broken. It's bruised, but it's a bad bruise. He wants to go into any fight 100 percent healthy. If Antonio Margarito happens to be the best available option when he is healthy, so be it.
"We are not turning down Margarito. I want to make that crystal clear. When and if he is the best available option for Floyd's next fight, that's the direction he will move in."