Fighters with the most one punch knockouts.

[IamInuit]

Michael Moorer is another under rated heavy handed hitter. I think he is one of the few that lost power moving up. LHW a monster puncher. HW solid puncher.

Manny Steward said he was the hardest puncher he'd ever seen in the weight area.

[Manju]

A literal 1-punch KO can be hard to find. Foreman's KO of Moorer looks like one, but was actually preceded by a big punch earlier. Julian Jackson may have had Terry Norris out on his feet after one punch, but it was the subsequent combo that put him to the canvas.

Marquez's KO of PacMan probably qualifies...iirc it was literally one punch that caught Manny coming in and then lights-out. But Manny had already hit the canvas in that fight, so how much did the accumulation of punches affect him?

Some famous body-blow KO's certainly qualify (Hopkins - ODLH; RJJ Virgil - Hill) but body blows are a tad different. It more about placement than power...the victim is usually still conscious.

So if we define a "clean" 1-punch KO as:

1. The victim has not absorbed an accumulation of punches
2. He's unconscious,
3. Only one meaningful punch lands in the sequence

Then this is probably the cleanest 1-punch KO that comes to mind:

[Master]

Nunn was not a one punch boxing ko artist that was a fluke. McCallum did the same against Curry.

[Freedom]

Nice KO from this week, Jhonny Gonzalez has a lot of one punch KOs: