Question: Which mixed martial artist was represented by Marc Roberts?
Sentence (from "Marc Roberts (sports agent)"): He has represented NFL players such as Antonio Freeman, Tyronne Drakeford, O.J. McDuffie, Jerry Porter, and Tyrone Wheatley, NBA players Bobby Jackson, Johnny Newman, and Derek Anderson, and World Champion boxers "Merciless" Ray Mercer, Shannon Briggs, Tracy Harris Patterson, Danell Nicholson, Charles Murray and Alex Trujillo.
Relevant evidence: Yes