Byrd began boxing at age 5. Williamson began boxing at age 25. Byrd had his first amateur bout when he was 10 and won 275 fights and a silver medal at the 1992 Olympics (165 pounds). Williamson had 120 wins as an amateur and turned pro in 2000.  Byrd is currently 38-2-1 (20 KOs) and Williamson is 22-3 (18 KOs).

Byrd and Williamson know each other quite well. Byrd used Williamson for sparring sessions for two fights: once in May of 2001 when he was preparing to face Maurice “Mo Betta” Harris and again when he was preparing to fight Andrew Golota in April 2004.  Williamson believes he has sparred nearly 200 rounds with Byrd.

Byrd is considered one of the most articulate boxers in the sport; however, he may have met his match in Williamson, who earned a master's degree (Master of Arts) in administrative services from University of Northern Michigan in 1998.

Out of the ring, Byrd is known for his sense of humor and pranks. Williamson was a standup comedian at Roxy's Nightclub in Phoenix for over a dozen appearances in 1992.

Since 2004, Williamson has fought five times to Byrd's two. Byrd's last fight was on Nov. 13, 2004, where he was knocked down by Jameel “Big Time” McCline in the second round but survived and fought valiantly to successfully defend his IBF crown, winning a tough split decision. Williamson fought on the same night, defeating former world champion Oliver “The Atomic Bull” McCall by unanimous 10-round decision. In his last appearance, DaVarryl scored a second-round technical knockout over Derrick “D-Train” Jefferson on April 30.