Mir (14-5, 12-5 UFC), a former UFC heavyweight champion, knocked out Mirko "Cro Cop" Filipovic at UFC 119 last September. Nelson (15-5, 2-1 UFC), the Season 10 winner of "The Ultimate Fighter" and the former IFL heavyweight champ, went the distance with Junior dos Santos at UFC 117 last August, losing a unanimous decision. He returns following knee surgery.
Mir and Nelson are both native Las Vegans and sometimes training partners. They faced each other in a submission grappling tournament eight years ago, won by Nelson.