from www.espn.com:/CLICK HERE for more…. Leon Spinks, who surprised the boxing world by beating Muhammad Ali for the world heavyweight title in 1978, died Friday night at age 67, according to the Firm PR, a public relations firm that represents him. Spinks, who had been suffering from prostate and other cancers for five years, died with his wife, Brenda, by his side, the firm said. The St. Louis native, a former Marine who won a gold medal as a light heavyweight at the 1976 Olympics, was just 13 months and eight fights into his pro boxing career when he stepped…