However, Spinks rose to boxing stardom by unifying the WBC, WBA, IBF, and The Ring and lineal welterweight titles on December 13, 2003, when he defeated Ricardo Mayorga by majority decision.

Spinks received star treatment during introductions, with rapper Nelly accompanying him into the ring and leading the crowd in a singalong.

On July 8, 2006, Spinks earned his fifth world title, the IBF Junior Middleweight Championship (also called Super Welterweight by some sanctioning bodies), in a fight with reigning champion Roman Karmazin at the Savvis Center.

[3] On March 27, 2008, in a fight with Verno Phillips at the Scottrade Center in St. Louis, Spinks lost the IBF Junior Middleweight Championship via controversial split decision.

On April 24, 2009, Spinks reclaimed the vacant IBF Junior Middleweight Championship in a close split-decision victory over fellow St. Louis native Deandre Latimore.

On August 7, 2010, after a five-month delay due to scheduling conflicts,[4] Spinks lost the IBF Junior Middleweight Championship in a fight with mandatory challenger Cornelius Bundrage at the Scottrade Center in St. Louis.