Diaz was one of the biggest UFC stars before his suspension in 2015. The Stockton native became a cult figure because of his attitude in the cage as well as in real life. He fought Anderson Silva and initially lost the bout but it became a no-contest after they failed drug tests.
Silva tested positive for steroids while Diaz had marijuana in his system. Bizarrely and controversially, Diaz received a longer ban than Silva despite the latter using PEDs. It cost him some of the best years of his career in a decision that many fans still resent (via Sportskeeda).