Nate “Rock” Quarry and his opponent for UFC 91, Demian Maia, have both tested clean for banned substances.

Both fighters join the list of Randy Couture, Brock Lesnar, Amir Sadollah (withdrew due to injury), Nick Catone, Jorge Gurgel, Aaron Riley, Mark Bocek and Alvin Robinson, all of whom passed pre-event drug tests administered by the Nevada State Athletic Commission.

These preliminary tests have been used to prevent the possibility of “cycling off” steroids and other banned substances.