Boxers with ATG chins who suffered KO losses in their prime?

[Clegg]

By KO loses I mean down for the count or so badly hurt the ref has to step in. So McCall crying vs Lennox doesn't count, Vitali's 2 loses don't, Chuvalo's stoppage vs Foreman doesn't count, because their chins weren't cracked. Also no body shot knockouts for the same reason.

Sugar Ray beating Fullmer, Mosely beating Margarito, Hearns beating Duran are 3 I can come up with. Any more?

[The Old LefHook]

Duran was not in his prime. He was still a great fighter, but his prime was well behind him. That shoots your premise right in the foot.

[IronDanHamza]

Not quite prime but **** Tiger vs Bob Foster

[Obtuse]

Hearns/Cuevas

[Willie Pep 229]

Billy Miske - 102 fights (43-3-2 or 73-13-16) - one KO loss - stopped/KD only once (in102 fights) by Dempsey - inductee to HOF.

[4truth]

Ali stopping Foreman.

[Flickergrab98]

Tex Cobb is is not an ATG by any chance, but he had a legendary chin that was able to withstand the likes of Earnie Shavers among others. So, it’s unbelievable that he once suffered a first round KO by some rando named Dee Collier.

[markusmod]

Tszyu had a very good chin when he suffered his first loss by stoppage. His next defeat didn't happen until his final career fight, due to exhaustion.

[Tatabanya]

Most obviously, Mike Tyson vs Buster Douglas.

[QueensburyRules]

Ali stopping Foreman.

- - Prob is George up at the 9sec mark and Ali down for 30 sec after the ref waved the fight and had to be carried to his corner.