Charles L. "Sonny" Liston, nicknamed "The Big Bear", was an American professional boxer who competed from 1953 to 1970. A dominant contender of his era, he became the world heavyweight champion in 1962 after knocking out Floyd Patterson in the first round, repeating the knockout the following year in defense of the title; in the latter fight he also became the inaugural WBC heavyweight champion. Often regarded as one of the greatest boxers of all time, Liston was particularly known for his immense strength, formidable jab, long reach, toughness, and is widely regarded as the most intimidating man in the history of the sport.

Floyd Patterson was an American professional boxer who competed from 1952 to 1972, and twice reigned as the world heavyweight champion between 1956 and 1962. At the age of 21, he became the youngest boxer in history to win the title, and was also the first heavyweight to regain the title after losing it. As an amateur, he won a gold medal in the middleweight division at the 1952 Summer Olympics. He is recognised as one of the best heavyweights of all time.