Strikeforce Challengers 18: "Gurgel vs. Duarte" drug test results are in from the Nevada State Athletic Commission, who today confirmed that all 10 fighters who were tested for illegal/banned substances have passed with flying colors.

Fighters that were tested, including Jorge Gurgel, Joe Duarte, Nate James, Pat Healy, Derrick Mehmen, Nah-Shon Burrell, Milton Vieira, Gian Villante, Mike Bronzoulis and Ronda Rousey, were all screened for performance enhancers such as steroids and drugs of abuse like cocaine and marijuana, among others.

Results from these battery of tests all came back negative.

Both Gurgel and Duarte were also tested out-of-competition but still came in clean for the Challengers main event on Fri., Aug. 12, 2011, from the Palms Casino Resort in Las Vegas, Nevada.

The fighters who were tested were randomly selected. However, athletic commissions often test the main event participants, as well as those who have failed drug tests in the past.

Strikeforce Challengers 18 featured lightweight scrapper Jorge Gurgel doing what he does best: standing and trading for three rounds against the venerable Joe Duarte.

Unfortunately it wasn't enough to get the job done thanks to some impressive takedown defense from the San Diego native, who picked up the unanimous decision win.

Heavyweight mauler Gian Villante got back into the win column by decisioning Keith Berry while Pat Healy roughed up Eric Wisely.

For complete "Gurgel vs. Duarte" results and blow-by-blow coverage of all the main card action click here and here.