According to the Nevada State Athletic Commission, all 17 “UFC 137: Penn vs. Diaz” fighters that were drug tested produced negative results.
Although 22 athletes participated in the show, only BJ Penn, Nick Diaz, Cheick Kongo, Roy Nelson, Scott Jorgensen, Hatsu Hioki, Donald Cerrone, Eliot Marshall, Brandon Vera, Chris Cammozzi, Francis Carmont, Ramsey Nijem, Danny Downes, Bart Palaszewski, Tyson Griffin, Dustin Jacoby and Clifford Starks were required to pee in a cup.
The contestants was screened for drugs of abuse and performance-enhancing substances.
The October 29th event took place inside the Mandalay Bay Events Center in Las Vegas.
Diaz dominated Penn in the pay-per-view’s featured attraction to earn next shot at UFC welterweight king Georges St-Pierre.