Nathan Donald Diaz is an American professional mixed martial artist, currently signed with the Ultimate Fighting Championship. Diaz is the younger brother of former Strikeforce Welterweight Champion, WEC Welterweight Champion, and IFC Welterweight Champion, Nick Diaz. Prior to signing with the UFC, Diaz competed in World Extreme Cagefighting, Strikeforce, and Pancrase. He has been in the UFC since winning The Ultimate Fighter 5. Diaz is tied with Joe Lauzon for the second most UFC bonus awards, with 15 in total. Nate Diaz, along with Conor McGregor, held the record for the highest UFC pay-per-view buy rate for their contest at UFC 202, until it was broken by UFC 229's buyrate.

Lightweight and welterweight fighter who won The Ultimate Fighter's fifth season. Conor McGregor's five-year unbeaten record came to an end when he was submitted in 2016.