The second World Boxing Super Series (WBSS) semifinal took place in Sochi on Saturday, February 3. Gassiev knocked out his opponent in the final round.
Gassiev will fight Ukrainian Oleksandr Usyk in the WBSS final in Jeddah, Saudi Arabia, on May 11.
A week ago, Usyk defeated Latvian Mairis Briedis and unified the WBO and WBC cruiserweight titles.
The winner of the fight will receive $10 million, pick up the Muhammad Ali Trophy and be crowned the cruiserweight division's first undisputed champion.