All right, since it's been a recent topic, let's settle it once and for good. Which is the most embarrassing? If you have another pick by the same boxer, just pick the one for the appropriate boxer listed and note it in your post. If you have another boxer entirely, write him in, but keep in mind that I skipped Walcott and Liston's near-dives as they were not major titlists. Finally, I have tried to be fair in my leading/context words. Chronologically: Floyd Patterson dropped by Olympic Gold Pete Rademacher in Pete's pro debut? 36 year-old Ali loses to Olympic Gold Leon Spinks in Spink's eight fight? 35 year-old Larry Holmes losses to Michael Spinks, coming up two weight classes? Evander Holyfield badly knocked down by club-fighter Bert Cooper? 38 year-old Mike Tyson looses to clubfighter Kevin McBride (or Danny Willams)? Lennox Lewis cold-cocked by fringe contender Hasim Rahmen? Wladimir Klitschko losses to high-end gatekeeper Ross Purity? Anthony Joshua stopped by borderline-fringe Andy Ruiz? Tyson Fury rises from knockdown to barely and controversially beat MMA star/debut Francis Ngannou? Usyk rallies from behind to controversially stop legendaryKick boxer Rico Verhouven?
I actually don’t find most of these particularly embarrassing. I voted for Wlad vs Purrity due to Purrity being a true journeyman, and Wlad being a champ and decorated amateur.
Most of your examples was with “past their best” fighters and a few that redeemed themselves (like LL losing to Rahman and Klit losing to Purity) so to me the answer is AJ losing to Ruiz in a fight he should of won, followed by Fury “losing” to Ngannou.
See Ruiz was a serious contender, so I don’t find that one too embarrassing, even with it being a colossal upset. I have more respect than most for MMA fighters in the boxing ring, especially at heavyweight. So that coupled with the expectation of Fury to underperform often and seeing how fat he was, I didn’t find that one too embarrassing either.. and again, Ngannou is a world class fighter and a freak athlete.
Joshua dominated Ruiz and then got caught and stopped. I'm not sure what was embarrassing about the "Performance". Usyk's "Performance" against Verhoeven was far more embarrassing comparatively, despite winning, because Verhoeven had much more success than what Ruiz had.