Gainer is a colleague and friend of fellow
Pensacola, Florida native
Roy Jones Jr., and often fought on his under-cards.
Featherweight champion In 2000, Gainer defeated
Freddie Norwood to win the
WBA featherweight title and after four defenses lost to
Juan Manuel Márquez, who became super champion, via technical decision in 2003.
Post title Since his defeat to Marquez, Gainer lost in a challenge to WBA titleholder
Chris John via unanimous decision. His last was a
split decision win over Carlos Navarro on the undercard of the Roy Jones-Anthony Hanshaw bout at the
Mississippi Coast Coliseum, in
Biloxi, Mississippi. ==Professional boxing record==