Floyd Mayweather Jr., left, stops Manny Pacquiao, from the Philippines, with a left during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Manny Pacquiao, from the Philippines, right, connects with a right to the head of Floyd Mayweather Jr., during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Floyd Mayweather Jr., right, pulls away from a punch thrown by Manny Pacquiao, from the Philippines, during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Manny Pacquiao, from the Philippines, right, throws a right against Floyd Mayweather Jr., during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Floyd Mayweather Jr., left, faces off with Manny Pacquiao, from the Philippines, during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Manny Pacquiao, left, listens to trainer Freddie Roach between rounds of his welterweight title fight against Floyd Mayweather Jr. on Saturday, May 2, 2015 in Las Vegas. (AP)
Floyd Mayweather Jr., talks in his corner between rounds during their welterweight title fight against Manny Pacquiao, from the Philippines on Saturday, May 2, 2015 in Las Vegas. (AP)
Floyd Mayweather Jr., left, hits Manny Pacquiao, from the Philippines, during their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Floyd Mayweather, Jr. of the U.S. lands punch against Manny Pacquiao of the Philippines (R) in the ninth round during their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
Floyd Mayweather, Jr. of the U.S. goes after Manny Pacquiao of the Philippines (L) in the first round during their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
May 2, 2015; Las Vegas, NV, USA; Floyd Mayweather (black/gold trunks) reacts after defeating Manny Pacquiao (not pictured) in their world welterweight championship bout at MGM Grand Garden Arena. Mayweather won via unanimous decision. Mandatory Credit: Joe USA TODAY Sports
Floyd Mayweather, Jr. of the U.S. celebrates defeating Manny Pacquiao of the Philippines in a unanimous decision following their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
May 2, 2015; Las Vegas, NV, USA; Floyd Mayweather celebrates after defeating Manny Pacquiao (not pictured) via unanimous decision during their world welterweight championship bout at MGM Grand Garden Arena. Mandatory Credit: USA TODAY Sports
Manny Pacquiao of the Philippines reacts after losing to Floyd Mayweather, Jr. of the U.S. following their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
Floyd Mayweather, Jr. of the U.S. poses with his title belts after defeating Manny Pacquiao of the Philippines in their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
Manny Pacquiao of the Philippines leaves the ring after losing to Floyd Mayweather, Jr. of the U.S. in their welterweight WBO, WBC and WBA (Super) title fight in Las Vegas, Nevada, May 2, 2015. (REUTERS)
Manny Pacquiao, from the Philippines, left, and Floyd Mayweather Jr., embrace in the ring at the finish of their welterweight title fight on Saturday, May 2, 2015 in Las Vegas. (AP)
Manny Pacquiao's wife, Jinkee, watches after Pacquiao lost his welterweight title fight against Floyd Mayweather Jr. on Saturday, May 2, 2015 in Las Vegas. (AP)