Marvelous Marvin Hagler stopped Thomas Hearns in a fight that lasted less than eight minutes yet was so epic that it still lives in boxing lore. Two years later he was so disgusted after losing a decision to Sugar Ray Leonard—stolen, he claimed, by the judges—that he never fought again. One of the great middleweights in boxing history, Hagler died Saturday at the age of 66. His wife, Kay, announced his death on the Facebook page for Hagler’s fans. “I am sorry to make a very sad announcement,” she wrote. “Today unfortunately my beloved husband Marvelous Marvin passed away unexpectedly at his home here in New Hampshire. Our family requests that you respect our privacy during this difficult time.” Hagler fought on boxing’s biggest stages against its biggest names, as he, Leonard, Hearns, and Roberto Duran dominated the middleweight classes during a golden time for boxing in the 1980s. Quiet …