That's when John L. Sullivan, once the bare-knuckle champion, became boxing's first-ever heavyweight champion under the Marquess of Queensberry rules. He held that distinction until his landmark fight with James "Gentleman Jim" Corbett in 1892. Following Corbett's 21st-round KO victory in New Orleans, the championship lineage that extends to today was established. As pro-wrestling legend Ric Flair says, "To be the man, you have to beat the man."