The Octagon returns to Las Vegas for an all-star doubleheader that will have the entire world watching. In the main event, world featherweight champion Conor McGregor moves to welterweight for an intriguing showdown with perennial contender Nate Diaz. This fight fan’s dream match-up pits the charismatic Irishman, fresh off a 13-second knockout of Jose Aldo, against Stockton, California’s Diaz, who has dismantled Michael Johnson and Gray Maynard in his past two victories. Plus, UFC women’s bantamweight champion Holly Holm looks to follow up her stunning knockout of Ronda Rousey with another big win, this time against Miesha Tate.