[5] Known as "The Blade", Barkley turned professional in December 1982, and first challenged for a world title against the highly skilled Italian Sumbu Kalambay, losing on points over fifteen rounds for the vacant WBA middleweight title in Livorno, Toscana, Italy in October 1987.

Barkley returned in 1988 with a split decision over Sanderline Williams and a fifth-round stoppage of Michael Olajide, before winning the WBC middleweight title with a third-round knockout of Thomas Hearns, voted 1988 Upset of the Year by The Ring magazine.

[6] Following the defeat to Duran, Barkley took on undefeated Michael Nunn for the IBF and lineal middleweight titles, dropping a close majority decision.

He next fought Nigel Benn in a challenge for the WBO middleweight title and was stopped on the three-knockdown rule at the end of a wild first round in which both fighters were hurt.

Barkley reportedly had trouble getting back down to the 168 lb weight limit and lost his IBF title via a corner retirement after nine rounds due to severe swelling around both eyes.

In 2008, at age 48, Barkley fought to a six-round draw in an unsanctioned exhibition bout against heavyweight Chauncy Welliver in Lapwai, Idaho at the Pi-Nee-Waus Community Center of the Nez Perce Tribe.

Through the support of the Bronx nonprofit BronxWorks and the Ring 10 boxing charity, he found housing and receives assistance so he can become self-supporting.