2011 Knockout of the year

[Mars_ax]

It's not KO of the year because the combatants were female but geez was brutal:
Holly Holm was out hanging on the ropes and the Ref let it go on?!? Really, really bad by the Ref letting it go that long

Wow, Rant, I hadn't seen this, Holly got destroyed, i'm really surprised.

[ruthless rocco]

mayweather v ortiz. loved it!

ortiz:
"here let me deliberately try to injure you. aww...i'm sorry bro. now lets make out."

mayweather:
"naw, i'm just gonna knock you the fuck out"

[Rantcatrat]

It's not KO of the year because the combatants were female but geez was brutal:
Holly Holm was out hanging on the ropes and the Ref let it go on?!? Really, really bad by the Ref letting it go that long

Wow, Rant, I hadn't seen this, Holly got destroyed, i'm really surprised.

Obliterated.

[Rantcatrat]

Here's a few more honorable mentions:

Kendall Holt vs. Julio Diaz (KO CLIP HIGHLIGHT) - YouTube

[Rantcatrat]

[Rantcatrat]

Gary Russell Jr. vs. Heriberto Ruiz - 1st round KO - YouTube

[Rantcatrat]

Zab Judah KO's Kaizer Mabuza - Round 7 - YouTube

[Rantcatrat]

Also for Dimitrenko's backward somersault after the KO.

Alexander Dimitrenko vs Albert Sosnowski 12 Runde - YouTube