Sports are a strange beast. It's one of the only professions a person can have where he's known by a nickname. There are instances where a player's nickname is known (and used) more than his real name. RGIII is possibly the best example of this phenomenon. His desire to be known by his suffix resulted in an NFL rule change, allowing the suffix to appear on his (and suddenly, every other player's) jersey.
Another profession where nicknames are looked on favorably is the military. There's Ol' Blood & Guts Patton, Stormin' Norman Schwartzkopf (although he preferred to be called The Bear), John J. "Black Jack" Pershing, and more locally, The Gray Ghost, John S. Mosby. We won't talk about William "Gonorrhea" Guarnere. He preferred the nickname "Bill".
Watch this video from USAA about some past and present NFL stars and their nicknames.