Usyk at Heavyweight has lost barely over a dozen rounds.

Chazz Witherspoon - 7 completed rounds, Usyk won 7 of them.
Dereck Chisora - 12 completed rounds, Usyk won 10 of them.
Anthony Joshua - 12 completed rounds, Usyk won 9 of them.
Anthony Joshua II...

Usyk at Heavyweight has lost barely over a dozen rounds.