When was the last time a HW champion had beaten 3 of his top 5 challengers?

Looking at the HW rankings atm and we have

Usyk
Fury
Joshua
Parker
Zhang
Dubois

Usyk has beaten 3 of that top 5 and both of his top two contenders.

When was the last time any HW champion could...

When was the last time a HW champion had beaten 3 of his top 5 challengers?