KO of the year: Holly Holm finishes Ronda Rousey

Whether you want to chalk it up to Holly Holm's perfect game plan, a mismatch of styles, Ronda Rousey's lack of preparation or all of the above, Holm's head-kick highlight will live on in MMA history.

A former world champion boxer, Holm (10-0) knocked out Rousey with a high left head kick in the second round of a UFC female bantamweight title fight on Nov. 14. She did it before a UFC-record crowd of 56,214 at Etihad Stadium in Melbourne, Australia, and she did it as a more than 8-to-1 betting underdog.

There was nothing fluky about this victory. Holm completely dismantled Rousey over six minutes, out-landing the undefeated champion in strikes 38 to 17. She even took the former Olympic judoka down at one point.

The final sequence featured Holm's best knockout shot in the high left kick. It marks the fastest knockout of her MMA career. Holm admitted afterward she was surprised the UFC called her number for the title shot so quickly (Holm is just 3-0 now in the UFC), but she said she never thought twice about accepting the fight. Good thing she didn't.

"It's hard to put yourself out there sometimes," Holm said, following the victory. "I know a lot of people thought it was early. I didn't expect the phone call to come this early, but I always look at it as, 'If you don't take the opportunities that are in front of you, how are you ever expected to get somewhere?' So as soon as it came, I said this is great, let's do it.

Honorable Mentions:

2. Conor McGregor, KO1/0:13 at UFC 194 on Dec. 12 vs. Jose Aldo

If this beats out Holm's head kick on your 2015 list, fair enough. Aldo has been the most dominant featherweight in the sport's history, and no one saw him going out like this. McGregor said before the fight that the Brazilian champion would be stiff and overcommit on the right hand. It took just 13 seconds for him to be proved right. It's the fastest finish in UFC title fight history.

3. Paul Felder, KO2/2:09 at UFC 182 on Jan. 3 vs. Danny Castillo

This fact wasn't as well known at the time, but the spinning backfist Felder used to put Castillo down in January is actually one of his favorite punches. The Philadelphia native has impeccable timing and instincts on that particular strike despite the fact he rarely throws it in the gym (too much of a hazard for his sparring partners).

4. Patricio Freire, KO2/0:32 at Bellator 145 on June 19 vs. Daniel Weichel

As knockout shots go, the counter left hook Freire used in this fight isn't overly impressive by itself. The punch came, however, amidst a flurry of punches from Weichel, who had Freire badly hurt. The featherweight title fight nearly ended in the first round, when Weichel dropped Freire with punches and the Brazilian had to be saved by the bell. This perfectly placed counterpunch kept the belt around Freire's waist that night.

5. Makwan Amirkhani, KO1/0:08 at UFC on Fox on Jan. 24 vs. Andy Ogle

From time to time, you'll see fighters take flight into a knee strike the moment a contest starts. Sometimes it works, often it doesn't. It worked for Amirkhani against Ogle in Sweden. The Finnish featherweight had the courage to throw it in his UFC debut, and it led to an 8-second finish. Had Ogle gone out from the shot (Amirkhani landed a few follow punches for the knockout), it might have been the fastest KO in UFC history.