If Briedis is close to as good as he was at cruiserweight at heavyweight, then I’d have him to win for the upset. I believe he’d avoid the bombs of Ibeabuchi, find a home for that uppercut and gain Ibeabuchi’s respect and proceed to outbox him from the outside with quick lead rights followed by combinations, the jab, landing counters and generally beating him to the punch and being able to move laterally and stay away from the returns, and fighting his way out when he needs to. This may be a controversial take, and is re why with Ibeabuchi being heavyweight proven, but this is how I see it playing out stylistically.
Briedis by a pretty competitive but clear UD. Ibeabuchi is a bit overrated and Briedis doesn’t really get the credit he deserves. At his best, he was elite and had a rock solid chin and nasty power.
He did. He beat the crap out of Charr, but won the WBC Silver cruiser belt less than a year later and won the real WBC belt right after that. He then basically spent his prime years fighting in the World Boxing Super Series for good money. He would've been chasing one big payday if he'd campaigned at heavyweight.
High risk low reward for guys who were in the rankings, beating Briedis wouldn’t have propelled them as he wasn’t highly ranked at HW, but also a high chance of them losing to Briedis and therefore losing their ranking, so he couldn’t get opportunities.
Or maybe he didn't have the confidence to succeed at HW. There nearly always higher paying fight at HW over Cruser
I don’t see why he wouldn’t though, and even if he wasn’t confident, surely he’d take the much bigger payday if it was there. He boxed once in a generation talent in Usyk which could’ve gone either way, and essentially dominated everyone else (except Noel Gevor) until he (Briedis) got old and lost close fights to a great fighter in Opetaia at 37 and an inactive 39. Only fight at HW he dominated and knocked Charr out cold. I don’t believe Briedis stylistically would’ve had issues at HW like Gassiev has.
Cruserweights outside of Holyfield and Usyk nearly all have issues though. Ibeabuchi was seen as a future long reigning champ before he went cracy and got locked up.
The cruiserweight division hasn’t historically had great fighters, and those who attempted to move up weren’t elite fighters. Haye moved up and did quite well, Mormeck was a come forward pressure fighter with no head movement, recipe for disaster for a cruiserweight moving up to heavyweight. Anyone else who attempted was nowhere near the level of Briedis, Briedis was an elite level fighter in terms of skill, and also was very well rounded and equipped to dealing with most situations, he could move, counter, pressure, lead off, jab, level change, move his head, fight on the inside, he’s not only well equipped stylistically for having success heavyweight, but he’s also elite, a combination which most Cruiserweights didn’t have.