Foster was an amateur boxing standout. He was the 1987 National Golden Gloves Light welterweight champion, and in 1988 the United States Amateur Light welterweight champion which led to a seed in the Olympic trials.
"Kid" Foster turned pro in 1989 and won his first 22 fights, setting up a bout with former champ Jimmy Paul in 1992. Paul won by an upset KO in the 7th round. In 1995 he challenged Hector Camacho for the IBC Welterweight Title, but lost via TKO in the 5th round. Foster later retired in 2001.