Nickolas Robert "Nick" Diaz (born August 2, 1983) is an American mixed martial artist who is currently signed with the Ultimate Fighting Championship. A two-time world champion, Diaz has been a professional competitor since 2001. In addition to the UFC, he has competed for PRIDE, Strikeforce, EliteXC, the WEC, DREAM, and Shooto. He is a former Strikeforce Welterweight Champion and a former WEC Welterweight Champion.