Nick Newell is an undefeated mixed martial artist, who is making his promotional debut at World Series of Fighting 4 on Aug. 10 in Ontario, Calif. He’ll be squaring off with Keon Caldwell. Newell also happens to be a congenital amputee, his left arm ending just after the elbow. Check out the NBC Sports feature Road to World Series of Fighting 4 , featuring an in-depth look at Nick Newell and how he became one of the hottest lightweight prospects in the MMA world.