The third man in the octagon for the lightweight title fight in the co-main event of UFC 181 on December 6th between champion Anthony Pettis and Gilbert Melendez will be John McCarthy. 
McCarthy was named the referee by the Nevada Athletic Commission on Monday and the commission also assigned Derek Cleary, Junichiro Kamijo, and Tony Weeks as the judges for the fight.
Prior to McCarthy being named the referee for this fight, the commission assigned Herb Dean as the referee for the main event title fight between welterweight champion Johny Hendricks and Robbie Lawler.
UFC 181 will come from the Mandalay Bay Events Center in Las Vegas on December 6th and the main card will be shown live on pay-per-view.
The current fight card is below.
Main Card: (PPV – 10 p.m. ET/7 p.m. PT)
Johny Hendricks (16-2) vs. Robbie Lawler (24-10, 1NC)
Anthony Pettis (17-2) vs. Gilbert Melendez (22-3)
Travis Browne (16-2-1) vs. Brendan Schaub (10-4)
Raquel Pennington (4-4) vs. TBD
Tony Ferguson (16-3) vs. Abel Trujillo (12-5, 1NC)
Preliminary Card: (Fox Sports 1 – 8 p.m. ET/5 p.m. PT)
Urijah Faber (31-7) vs. Francisco Rivera (10-3, 1NC)
Eddie Gordon (7-1) vs. Josh Samman (10-2)
Corey Anderson (4-0) vs. Gian Villante (12-5)
Todd Duffee (8-2) vs. Anthony Hamilton (12-3)
Preliminary Card: (Fight Pass – 7 p.m. ET/4 p.m. PT)
Sergio Pettis (11-1) vs. Matt Hobar (9-2)
Alex White (10-1) vs. Clay Collard (13-5, 1NC)