Keith Thurman beats Luis Collazo, then calls out Floyd Mayweather

— -- TAMPA, Fla. -- Keith Thurman, hailed by many as boxing's next big star, may not have had his best night but it was good enough to retain his welterweight world title in a dominant eighth-round knockout of former titleholder Luis Collazo on Saturday night in the debut of Premier Boxing Champions on ESPN at the USF Sun Dome.

Collazo, with blood pouring from a terrible cut over his left eye, said after the seventh round that he could not see out of it, and the fight was stopped one second into the eighth round.

Thurman retained his belt for the second time and then called out the pound-for-pound king and recognized welterweight world champion Floyd Mayweather, who is looking for a Sept. 12 opponent.