Hagler vs. Hearns (1985)

Marvelous Marvin Hagler vs. Thomas Hearns, fought on April 15, 1985, is celebrated for its furious opening round, which many boxing analysts consider the greatest in history. Hearns reportedly broke his right hand in the first round but continued to fight, landing a powerful right hand that Hagler later cited as the hardest single shot he ever took. Despite the injury, Hearns continued to fight for several more rounds in a bout ultimately stopped in the third round.