The Ukrainian won with the judges scoring the fight 120-108, 119-109 and 119-109
Oleksandr Usyk has become the first man to unify all four world cruiserweight titles by beating Murat Gassiev in Moscow.
The Ukrainian was awarded a unanimous victory – 120-108, 119-109, 119-109 – and his win also means Usyk wins the inaugural World Boxing Super Series Ali Trophy.
Gassiev, the Russian, held the WBA and IBF titles heading into the fight, with 31-year-old Usyk becoming the first man to unify all four world titles at that weight class, having already been WBO and WBC champion.
This bout, the World Boxing Super Series final, was originally set to take place in May, but was pushed back after Usyk suffered an elbow injury.
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