Are you joking? His chin is famously cast-iron, among the best ever. One fluky moment in a career spanning that many years and that many divisions doesn't disprove that nor a "mystery" make.
I'm not sure on this as Beterbiev hasn't had nearly as many fights to gauge against different styles. I don't think either man get's knocked out as Tony's chin was solid. yes he could get hurt but never stopped so... Tony could be lackluster against average opposition but this is prime for prime. So I would go with Beterbiev on a UD at Light Heevy but would go with Tony who was better at Crusier also a UD.
To quote the big man himself he was "Undestructable" No one is stopping Tony even armed with a baseball bat.
Toney lost or almost lost to worse fighters than Beterbiev. But best version vs best version, Toney outboxes and possibly stops him via constant countering.
How much does Peter weigh? So 92 fights at 4 weight divisions never stopped..... So James "never stopped in 92 fights" Tony is now chinny according to you? Log off son boxing isn't for you. Try Mumsnet.com
He was never stopped though was he? You'll know when I'm seething...... As your eyes will be rolling in the back of your head and you would have solied yourself (again) wandering what on earth just happened to you....