Even Usyk would have a really tough time because in all likelihood he'd have to survive the full 12 rounds to win, as skilled as he is and as good as his chin is, thats a long time against a 6'7 guy with insane one shot KO power.
Usyk isn't that much higher skilled or tougher than Glowacki or Briedis.
He choosed against them right tactique and they against him picked wrong Solutions for first rounds, thats all.
Plus Usyk is more marketable and with good PR team.
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OK, let's theoretize dreams, because they will not be in HW anyway.
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Against a boxer with considerably better reach and a good punching skills these boxers doesn't have that much chances in long range exchanges.
What then is doable?
To catch with counterpunches, this is easier if wide amplitude punches are thrown and enough opening in this moment.
Or get closer, especially if one does have a good clinch game.
This in CW exactly Briedis does have and looks that exactly this might be most suitable tactic….
Not Usyk, he likes outbox from distance a lot and with an opponents that does have better reach than he this will not be easy.
Against Ruiz a CW boxer that loves clinch game have less chances to use it: heavy, some 255-270 lbs, too heavy for him to torture in clinch. Stocky with good core covered with fat: from close distance damage his core looks hard task too. Short reach in close distace isn't disatvantage + Ruiz is good counter puncher, both hands are seriously dangerous.
there Usyk does have better chances won Ruiz by points in AJ manner, if didn't allow close distance and didn't seriously attempted to KO him.
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Briedis def is able to defeat anyone from HW top IF they do mistakes but he def can't won for example 3-4 TOP HWs in row I think.
The same about Dorticos and Glowacki, but their clinch game isn't that good.