It has to be Ali losing to Spinks - a guy outweighed by two stone, with only 7 professional fights who would be a cruiserweight by today's standards. After losing to Ali in the rematch, Spinks fought Coetzee and look what happened.
I don't think there's anything AJ can do now to be considered an ATG. He's been too poor for far too long.
Welcome to my World Clinton. I recently posted about Ken Norton being a southpaw. Back to the naughty step !
Isn't the thread title... "Which ATG heavyweight has the worst loss" Is ATG an acronym for something other than All Time Great ?
Wlad lost two rounds. Fury lost one. The rest were all ****. Come to think of it, even those three rounds were pretty shitty too. Second worst fight in HW championship history.
I concur with all those saying Alis loss to Spinks, yes he was still on his feet, but that in my opinion makes it worse, as a lucky punch can put you down for 10, however for The Greatest with all his big fight experience to not be able to win against Leon Spinks, with his lack of pro bouts and weight differential over 15 rounds was shocking. However as i have said previously, seeing the image of Leon held aloft arms raised and with his gaped teeth grin on announcement of the result, was for me at the time being a teenage recruit in basic training, a true 'Rocky' moment, ah memories.
Norton was an elite fighter in a golden era and it took the Ali fight to finally shine, no where near the WORST atg loss.