Nixon started his college career at Grambling State University where he was a wide receiver on the school’s football team. When Grambling’s head football coach Doug Williams left the program, Nixon moved on to Howard Payne (NCAA Division III) to play football. During a football game, the school’s track coaches saw how quickly Nixon ran down a ball carrier. That is when he was asked to go out for the school’s track team. Nixon joined the track squad two months into the season and did well, qualifying for the NCAA Division III Championship that year, where he won the 200m and finished third in the 100m. During that period of time Howard Payne closed down its track program, except for Nixon, who went on to win NCAA Division III 100m and 200m national titles in his second season. He eventually tried the 400m after acknowledging that his start out of the blocks for the shorter dashes left little to be desired. Nixon is coached by Terry Wilson of Long Beach Wilson High School in Southern California and Quincy Watts, the 1992 Olympic 400m and 4x400m relay gold medalist.