UFC Hall of Famer Daniel Cormier will take part in an upcoming WWE event. The feud between  Seth Rollins  and  Matt Riddle  has been pretty heated, and even in a Fight Pit match at Extreme Rules, may get out of hand. A normal referee may not be able to keep things under control, but what about a former two-division UFC Champion? That’s exactly what the match will have on Saturday, Oct. 8 in Philadelphia. Ariel Helwani broke the news on Saturday night that Daniel Cormier, the former UFC Light Heavyweight and UFC Heavyweight champion, will serve as guest referee when Rollins and Riddle square off in the Fight Pit.