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Jess Willard

1915-19

At 6-foot-6½, Willard held the distinction of being the tallest heavyweight champion in history for nearly 100 years. A working cowboy, "The Pottawatomie Giant" took up the sport at age 27, eventually knocking out Jack Johnson in 1915 to win the title in Cuba. Willard defended the title just once in the next four years.

Then, in 1919, Jack Dempsey overcame a 58-pound weight disadvantage to knock down the 37-year-old Willard seven times in the first round en route to a third-round TKO. Willard reportedly suffered a cracked skull, broken ribs, a shattered jaw, a broken nose, missing teeth and partial hearing loss in a savage beating.