Ray Leonard, Marvin Hagler, and Thomas Hearns were three of the boxing legends known as the Four Kings of boxing. These three fighters, along with Roberto Duran, dominated the boxing scene in the 1980s. They fought each other multiple times, producing some of the most memorable fights in boxing history. Duran beat Leonard in their first fight, before losing the second and third bouts. Hagler and Hearns also fought each other, with Hagler winning in a classic three-round war. Although they were fierce rivals in the ring, the Four Kings were also great friends outside of it, with a deep mutual respect for each other's skill and grit.