Eddie Hearn tweeted that he received a letter from the IBF ordering Oleksandr Usyk (20-0, 13 KOs) Defend heavyweight belt with mandatory challenger Filip Hrgovic (15-0, 12 KOs).
Hrgovic gained challenger status in August by defeating Zhang Zhilei in Saudi Arabia. At the same event, Usyk defended his WBA, WBO and IBF titles against Anthony Joshua.
Oleksandr Usyk planned to return to the ring in March with a unification fight with WBC champion Tyson Fury (32-0-1, 23 KOs), but in light of the IBF directive, this fight is now in doubt.
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