Ultimate Fighting Championship (UFC) held a press conference recently for its upcoming UFC 146: "Dos Santos vs. Overeem" event scheduled for May 26, 2012, at the MGM Grand Garden Arena in Las Vegas, Nevada.

Immediately after the presser wrapped, the Nevada State Athletic Commission (NSAC) decided to drop by and surprise the six heavyweights in attendance -- Junior dos Santos, Alistair Overeem, Cain Velasquez, Frank Mir, Roy Nelson, Antonio Silva -- with an impromptu drug test.

Gotta keep these big boys on their toes and all.

In lieu of being nervous, though, a few of the fighters cheesed for Roy Nelson's camera while waiting for "results of our pee tests," as Nelson so eloquently worded it. And while results have yet to be released publicly, it certainly appears as though all systems are clear for the UFC's annual Memorial Day weekend event.

At least if we assume they wouldn't be so damn happy knowing they were about to fail. For his part, "Big Country" simply said, "I hope I pass." Right.

For more on the surprise drug test at the UFC 146 press conference click here, and for all the latest UFC 146 news and notes click here.