Marvelous Marvin Hagler (born Marvin Nathaniel Hagler; May 23, 1954 – March 13, 2021) was an American professional boxer and film actor who competed in boxing from 1973 to 1987. He reigned as the undisputed champion of the middleweight division from 1980 to 1987, making twelve successful title defenses, all but one by knockout. Hagler also holds the highest knockout percentage of all undisputed middleweight champions at 78 percent. His undisputed middleweight championship reign of six years and seven months is the second-longest active reign of the last century.