Terry Norris vs Stevie Little. That was as one punch as it gets because Little was making Norris miss badly. I don't think Terry had landed a punch in two rounds leading up to the right hand that ended the fight.
Another one the Brits in particular might remember: Wayne Alexander flattening Mehrdud Takaloo. Made all the more impressive by the fact that Alexander had just been hurt, was on the back foot and under siege when he found a left hook from nowhere to end it. You simply couldn't find a sweeter spot to land a shot like that and it absolutely annihilated Takaloo. Well worth a look for anyone who hasn't seen in. Speaking of left hook, one-punch knockouts, I've got to five an honourable mention to Donaire-Darchinyan I. Such a perfectly-executed shot, it didn't have to travel very far at all. Plus, it was the springboard for the career of a guy who has been one of my favourites ever since.
Marciano- Walcott 1 actually made me go "guh" when I saw the right land. If that isn't a resounding endorsement I don't know what is.
Marciano throwing the kitchen sink at Walcott for 12 and then getting the "1 punch" ko in the 13th...
My favorite to this day. I watched a clip on CBS Sports Saturday reviewing from the previous night, just hours before Hagler KO 5 Obel Hagler at his peak. Reading about the fight his manger supposedly said "he's a punk" to which Marvin replied "I like 'em like that. I'm gonna hurt him Pat"
Hearns vs. Duran, although Tommy vs. Duran was not a one punch knockout. One punch ended the fight but Duran was wobbly after a barrage of punches.. Besides the Hearns fight, the pure one punch knockout I like the most is Mike McCallum vs. Donald Curry. One moment a fight and the next Donald is on his back.
Some people might not notice, but that one-two punches that Lennox threw in rematch against Rahman was the same exact combo that he threw against Mccall right before Mccall landed that right hand. Stewart certainly a brilliant trainer and has studied Lennox, cause Mccall easily dodged those one-two and countered right away.
Bit of a niche one but Kennedy McKinney dropping Welcome Ncita in round 11 after having nearly been stopped earlier in the round. Ncita dropped like a stone from that one.
If you had to explain to someone what a one punch knockout was, you'd just show them that clip. Reggie Johnson - William Guthrie was perfectly timed and completely unexpected. Virtually all of Reggie's world-level fights at 160 had went the distance, and he iced a much larger power-punching light-heavy with one punch.