1) Dan Henderson vs. Michael Bisping (UFC 100)

During the filming of "The Ultimate Fighter: US vs UK", a heated rivalry began brewing between coaches Dan Henderson and Michael Bisping. The build-up of the feud was put into living rooms across the country leading up to UFC 100 in July. Henderson, who had been open about his distaste for Bisping while filming, got his revenge on the biggest stage in UFC history. Henderson dominated the first round by cutting off the Octagon and making Bisping circle dangerously toward his power hand. The second frame saw more of the same, only this time Bisping would not hear the closing bell. After feigning a leg kick, Henderson landed a crushing right hand on Bisping’s chin that turned the Brit’s lights out entirely. Adding insult to injury, Henderson then followed Bisping to the ground with a diving punch reminiscent of professional wrestling, and earned what was, by far, the most brutal knockout of the year.

2) Fedor Emelianenko vs. Andrei Arlovski (Affliction: Day of Reckoning) In what was a clash between the two top-ranked heavyweight fighters on the planet, Fedor Emelianenko proved once again that he is indeed the greatest heavyweight of all time. As story played out at Affliction's "Day of Reckoning" this past January, Andre Arlovski used his superior boxing skills to frustrate Emelianenko early on, keeping ‘The Russian Experiment’ on his heels for the first three minutes of the fight. After landing a powerful straight kick which pushed Fedor into the corner, Arlovski attempted to follow with a flying knee. Fedor had had enough at that point. While Arlovski was still in mid-air Emelianenko landed a thunderous overhand right which sent ‘The Pitbull’ crashing to the mat face first, in one of the most visually stunning knockouts in MMA history, at 3:13 of the first round.

3) Lyoto Machida vs. Rashad Evans (UFC 98) Without a doubt, now UFC Light Heavyweight Champion, Lyoto Machida had a banner year in 2009. Riding high off a devastating first round knockout victory of previously undefeated Thiago Silva, ‘The Dragon’ met Rashad Evans at May's UFC 98 and added another victim to his win column. After controlling the action in first round, dropping Evans, Machida proved that his "elusive" style did not simply mean backing away. The champion came out for blood in the second frame, absorbing no damage, while repeatedly tripping and dropping Evans. Machida ended the fight when he landed a devastating combination of punches that sent Evans crumbling, unconsciously, against the cage and to the canvas at 3:57 of the round. The "Machida Era" had begun.

All Ten Knockouts: Source

Some really good MMA went down this year, and some amazing knockouts - that's for sure. It makes my brain hurt, in a good way.