By Edward Chaykovsky

After Floyd Mayweather Jr. (48-0, 26KOs) unified the WBO/WBC/WBA welterweight titles with a twelve round unanimous decision over Manny Pacquiao on May 2nd - British star Amir Khan appeared to be the frontrunner to face Mayweather on September 12th at the MGM Grand in Las Vegas

In the last few days, former IBF/WBC welterweight champion Andre Berto is being widely reported as the frontrunner to face Mayweather in a fight potentially taking place on CBS.

Even Khan has already acknowledged that Berto is the likely candidate to get Mayweather in September.

Jeff Mayweather, who is Floyd's uncle, believes Khan killed his chances to get the fight because of his high volume of public challenges to Mayweather - where he often claimed the pound-for-pound king as running scared.

"I think he killed the fight, because he started talking too much. It got to the point where he probably got under Floyd’s skin enough for him to say - 'f*** you, I’m not giving you a fight, not because I can’t beat you, just because I’m not gonna give you the payday like everyone else is begging for.' Amir Khan started acting like Floyd needed him. Really? He needs you? For what?," Jeff told On The Ropes Boxing Radio .