How to affect and hurt an opponent without landing any punches? Feint them! Feinting is a lost art in boxing and very few boxers feint enough or properly today. Usyk is one of the few boxers today who still utilizes that art / skill to full effect. Usyk's feints / probes with his lead hand, and with his footwork, really unsettled Bellew as can obviously be seen. The reason why Bellew became tired and fatigued, was MOSTLY due to Usyk's feints that forced Bellew to move more than he was comfortable doing. Usyk's feints forced Bellew to move his head to avoid fake punches that weren't even there, forced his body to move to avoid fake punches and step-in attempts that weren't even there and forced him to throw counter punches, especially with the right hand to fake punches that weren't even there. All of this increased the rate at which Bellew gassed. In actual fact, Usyk's feints were hurting Bellew, more than Bellew's punches were hurting Usyk. Bellew's own power counter punches, even the ones that landed on Usyk, hurt himself more than they hurt Usyk because Usyk took most of the sting off those punches by bracing for those punches, whilst Bellew was only wasting energy and causing himself to be further tired with those ineffective punches. So Bellew's supposed success with his counter punches and power right hands were totally overrated. Since they only led to his own demise, and had pretty much no effect on Usyk whatsoever. Just look at Usyk's face after the fight. Barely even a mark, and for a reason. Since Usyk rendered Bellew's punches ineffective. So those who think Bellew out-boxed Usyk in the early rounds and that somehow is suppose to prove Usyk got exposed, need to think again! Since in reality, Usyk was inflicting greater harm on Bellew than vice versa in those rounds. Even though it may have looked like Bellew was winning those rounds.
Usyk traps you into thinking that you have to match his workrate The whole time you're reacting to Usyk's feints he is figuring out how you react to certain situations and punishes you for it. Lomachenko does the same thing.