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Oleksandr Usyk defeated Anthony Joshua in September 2021 to unify the cruiserweight world titles and become a world heavyweight champion. Usyk, a former undisputed cruiserweight champion, was considered a significant underdog going into the fight, but he dominated Joshua from the opening bell and won by unanimous decision. The victory was a major upset and cemented Usyk's status as one of the best heavyweight boxers in the world.