UFCs All-Time Top 10: #3, UFC 166 watches Melendez and Sanchez turn in an all-time classic, Velasquez claims his spot as MMA's undisputed best heavyweight

Every once and awhile, an Ultimate Fighting Championship (UFC) card comes around that reminds me of why I first got so obsessively interested in this mixed martial arts (MMA) business in the first place.

Sure, historically significant matches are all fine and good, as are heated blood feuds hyped up by scathing interviews straight out of pro-wrestling's territorial days.

However, all of the Chael Sonnen-style promos in the world wouldn't amount to a hill of beans if fighters didn't sometimes deliver moments of transcendental greatness inside the cage.

And if what you're looking for is a card that delivered more than its share of memorable moments, you'd be hard pressed to find one better than this past October's UFC 166.

As is so often the case with shows that end up being complete barn burners from start to finish, UFC 166 didn't look like much on paper. Sure there was the Cain Velasquez vs. Junior dos Santos rubber match for the heavyweight title, and a lightweight tilt between Gilbert Melendez and Diego Sanchez that looked like fun, but of the UFC's big three pay-per-views (PPV) remaining in 2013, UFC 166 appeared to be the calm before the storm.

But then a funny thing happened. Fight after fight on the night of Sat. Oct, 19, 2013, the competitors inside Houston's Toyota Center turned in one fantastic match after another.

It started on the undercard when Kyoji Horiguchi laid a beating on Dustin Pague en-route to a second round technical knockout in an all-action opener that streamed on Facebook and UFC's YouTube channel. The next three unaired prelims also delivered decisive finishes and plenty of fireworks.

Then on the FOX Sports 1 (FS1) "Prelims," things got really good.

To be honest, K.J. Noons vs. George Sotiropoulos wasn't anything special, but Sarah Kaufman vs. Jessica Eye more than made up for what the televised opener lacked in excitement. Both ladies turned in a gutsy, back-and-forth brawl that saw Eye walk away the winner in a controversial decision.

In the next bout, Hector Lombard put the rest of the 170-pounders in the UFC on notice when he brutalized Nate Marquardt en route to a vicious knockout victory.

Then in the FS1 main event, C.B. Dollaway and Tim Boetsch had a hell of a fight that ended in controversy when Boetsch got the win by decision in a fight the "Doberman" clearly dominated.

The PPV portion of the card kicked off with John Dodson vs. Darrell Montague in a flyweight contest. At first, neither man was willing to commit to his strikes, but that changed in a big way once Dodson finally opened up midway through the round. He rocked Montague with punches until turning out his lights completely with a hand grenade of a straight left. Dodson ended up pocketing $60,000 and winning "knockout of the night" honors for his troubles.

The finishes kept coming in the next fight, when Gabriel Gonzaga knocked out Shawn Jordan in just a little over a minute with a right hook that set up a brutal series of consciousness-severing hammerfists.

And then things got really great.

Gilbert Melendez vs. Diego Sanchez may have been many people's pick for "fight of the night," myself included, but nobody could have predicted it would end up being one of the all-time classic fights in MMA history.

The bout started off action packed from the start, but late in the first round Sanchez -- who was clearly a step behind his faster, more technical opponent in the stand-up department -- initiated a crazy exchange and Melendez was only too willing to stand and trade with him.

The second round was all action, with both men eating career-shortening punches and coming back for more like each thunderous hook was nothing more than a playful love tap from a first-grader.

Sanchez was clearly down on the scorecards heading into the third, when his corner invoked his young daughter's name, and told him Melendez was trying to steal food from her mouth. That did it. Sanchez came out like a one of those dudes on angel dust you see on COPS sometimes, and -- blood streaming down his face from a massive cut above his eye -- relentlessly threw punch after punch at Melendez.

Once again Melendez was more than up for the task of matching Sanchez blow for blow, and they ended up slugging it out in a display of fortitude and will that will be remembered up there with Forrest Griffin vs. Stephan Bonnar I, Don Frye vs. Yoshihiro Takayama, and Dan Henderson vs. Mauricio Rua.

Although Melendez may have earned the unanimous decision victory, it really was the kind of fight where, as the cliche goes, there was no real loser. Both men walked away from the fight a bigger star than they were going into it, and Melendez is now primed to once again contend for the lightweight title.

If I'm being real, the Daniel Cormier vs. Roy Nelson co-main event was kind of a dud. It wasn't exactly boring, but after the shot of adrenaline that was Melendez vs. Sanchez, watching Cormier control Nelson in the clinch wasn't exactly my idea of a thrill-ride.

Then in the main event, Cain Velasquez and Junior dos Santos delivered yet another memorable battle to cap off their trilogy. It may have been more of a protracted beatdown on Velasquez's part than anything else, but the heart Dos Santos showed in steadfastly attempting to search for the victory, even when he was clearly outmatched, helped make this one of the more exciting heavyweight title fights in recent memory.

When it was done, Velasquez had proven beyond all question that he was the better man than Dos Santos, and likely the best heavyweight fighter of his generation. Perhaps given more time, UFC 166 will appear as a pivotal turning point in the company's history, seeing how it represents Velasquez proving his dominance over the second best heavyweight of the era.

Of course that's provided Velasquez's body holds up to the rigorous abuse he puts it through in training, which is far from a sure thing.

Sitting here a little under a month after the event, it may be hard to properly evaluate UFC 166's place in history, but as of right now, it certainly feels like the best top-to-bottom all-action card the company has ever produced.

One thing's certain though: no matter how you slice it, UFC 166 provided a killer night of action that fans will enjoy for years to come.