Diaz made his debut for EliteXC in Hawaii on September 15, 2007 on Showtime. He won a hard-fought split decision over his opponent Mike Aina. MMA Weekly reported that Nick Diaz signed a two-year deal with EliteXC and in his next fight, fought striking specialist KJ Noons for the vacant 160 pound title. Once the fight began, the two exchanged rather evenly on the feet until Noons dropped Diaz with a well timed right counterpunch. Diaz attempted several takedowns, all of which were stuffed by Noons, on one occasion with a swift right knee which opened up a notable gash on Diaz's face, eventually resulting in a loss via doctor stoppage due to multiple cuts on his forehead. A disappointed Diaz left the arena immediately and on his way out he flipped off the doctor from the arena entrance and shoved the camera out of his face.