Weatherspoon attended Fort Lewis College, where he also played basketball as a guard, after transferring from Mesa Community College.[1][2][3][4][5] He was drafted by the Saints in the 13th round of the 1972 NFL draft with the 320th overall pick.[2][6][7] The Saints said of him that he is "A quick starter who can accelerate rapidly – and he can make nifty moves at top speed (4.6)...He has quick hands and feet and an excellent attitude."[8] The Saints waived him towards the end of the preseason but then signed him to their taxi squad.[9][10] He was activated for the Saints' November 8 game against the Minnesota Vikings when linebackerRay Hester and running backArthur Green were injured and played mostly on special teams.[11][12][13] He was returned to the taxi squad after the game.[14][13]
Saints' coach J.D. Roberts felt that Weatherspoon had improved going into the 1973 preseason.[15] But Roberts was fired during the preseason, and Weatherspoon was cut without playing a regular season game that season.[16] In 1974, he signed with the Denver Broncos but was cut before the season began.[17][18]
In 1975, Weatherspoon signed with the Southern California Sun of the World Football League along with his brother Ed, a defensive back who had previously been with the Houston Oilers during the 1973 preseason.[19][20][21] Cephus was traded to the Vulcans at the end of July, just before the regular season began.[22] In the opening game against the Chicago Winds on August 2 he caught a 53-yard pass from Matthew Reed to set up the Vulcans' only touchdown in their victory.[23][24] That was to be Weatherspoon's only reception as a pro.[25] Ed remained with the Sun, where he intercepted two passes and returned two punts before being waived in September.[26][27] The league folded before the end of the 1975 season. In 1976 and 1977 Weatherspoon played semi-pro football.[28][29]
In 2012, Weatherspoon joined a lawsuit against the National Football League alleging concussion-related injuries from playing.[30]