The undisputed heavyweight champion brushed off suggestions of retirement and named several contenders for his next fight

LONDON -- Oleksandr Usyk knocked out Daniel Dubois in the fifth round and became the undisputed world heavyweight champion for a second time on Saturday. The undefeated southpaw retained his WBA, WBC and WBO belts and regained the IBF belt he relinquished just over a year ago.

Unified heavyweight champion Oleksandr Usyk hasn't just fought (and defeated) the very best of his era, when it comes to former champions Anthony Joshua and Tyson Fury, he has done so twice.  So, it's only natural that when Usyk (23-0,