The Main Event. The main event is the epitome of prize fighting. It’s the big money fight and the one that everyone is itching to see. It is often the best and most hyped fight on any UFC card. Most main events are title fights or fights between some of the top fighters in their division.

The undercard. The undercard is home to hungry fighters or wily veterans trying to make a name for themselves, grow in the sport or return to past glory. The undercard is basically the collection of fights leading up to the main event, essentially in place to keep people entertained until the “big” fight. These fights often hold much less hype and therefore, fans aren't shocked when the fights are not especially good or memorable in any way.

Now, on most nights, these fights live up to their labels with main events getting all the glory and being the better fight, and the undercards falling behind. This doesn’t shock anyone as it is what is supposed to happen on any given fight card.

But every so often, the fans are blessed with an anomaly. This anomaly is an undercard fight that absolutely shocks the world and takes the headlines away from those greedy main events. Whether it be Edson Barboza kicking Terry Etim’s head all the way to Mars, Gilbert Melendez engaging an a slugfest for the ages with Diego Sanchez, or Matt Grice and Dennis Bermudez putting on one of the best fights of all time, this list will cover 15 of the greatest under card fights in UFC history, that without a doubt went above and beyond their cards main event.

15 15. Yoel Romero vs. Tim Kennedy at UFC 178

This was a back and forth war between two of the best Middleweights on planet earth, both within a win or two of a title shot. Things really heated up when Kennedy absolutely rocked Romero at the end of round two and was within seconds of beating him before the round ended. Romero then came out guns blazing in round 3 and picked up an early TKO in round 3. This fight was much better than the main event that featured a hugely outmatched Chris Cariaso against the Flyweight king and top 5 pound for pound fighter, Demetrius Johnson.

14 14. Abel Trujillo vs. Jamie Varner at UFC 169

This was booked as a striker vs. striker match up between two men with extremely aggressive and violent styles inside the cage. The fight didn’t disappoint as both men were rocked and drowsy throughout the fight, with both coming close to victory. Ultimately, Trujillo had the last laugh as he connected with a vicious right hook that put Varner out. The main event on this card featured Renan Barao vs. Urijah Faber for the Bantamweight title. This main event didn't even get close to living up to expectations as it wasn’t much of a fight as Barao dominated en route to a first round win.

13 13. Edson Barboza vs. Terry Etim at UFC 142

Wow. That is all that can be said about this one. This fight began about as interesting as most undercard matches, which is not very. Etim was winning a fairly forgettable fight until early in the third round. Then it happened. Edson Barboza landed a picture perfect spinning wheel kick that had Etim out cold before he even hit the ground. It was the first wheel kick KO in UFC history and was among the best KOs of all time. The main event of this card featured a Featherweight title fight between Aldo and Mendes. This fight was actually very good and lived up to the hype, but nothing can compare to what Barboza did that evening.

12 12. Carlos Condit vs. Rory Macdonald at UFC 115

This fight featured a young up and comer in Rory Macdonald and an established Welterweight contender in Carlos Condit. The way this fight progressed shocked even the most seasoned UFC fans. Macdonald, the 21 year old prospect in his second UFC fight, was dominating the action and was on the way to a victory. In the third round, however, Condit was done messing around and finished Macdonald in the final ten seconds for the huge comeback win. The main event of this card was extremely weak as it featured an over the hill Chuck Liddell being knocked out by Rich Franklin.

11 11. Chuck Liddell vs. Wanderlei Silva at UFC 79

Speaking of Chuck Liddell, he is the focus of number 11 on the list. This fight between Liddell and Silva was more than a decade in the making, and it was one of the most highly anticipated fights among PRIDE and UFC fans alike. The fight did not disappoint as it was three solid rounds of back and forth action that satisfied the appetite of the fans. The main event featured two great fighters in GSP vs. Matt Hughes, but that fight didn’t have the aura or mystique of the Liddell/Silva matchup. GSP won by submission.

10 10. Joe Lauzon vs. Jamie Varner at UFC on Fox 4

Jamie Varner makes his second appearance on the list, this time at number 10. This fight featured Varner and Joe Lauzon, who has more post fight bonuses than anyone else in UFC history, so you knew this was going to be a great one. The fight began with Varner getting the upper hand, which was then quickly answered by Lauzon. It continued this way until Lauzon picked up a brilliant triangle choke submission to seal the victory. The main event featured a fight between Shogun Rua and Brandon Vera that was a fight that can be summed up with one word, meh.

9 9. Pedro Rizzo vs. Josh Barnett at UFC 30

This fight between Rizzo and Barnett is often credited as the first real, solid and action packed UFC Heavyweight fight. Most Heavyweight fights before this were contested between men with very limited gas tanks. But not this fight. Both Rizzo and Barnett stood toe to toe for the better part of the fight before Rizzo finally finished Barnett with a hellish right hand. The main event of this card pitted Tito Ortiz vs. the late Evan Tanner. This was a lackluster main event as Ortiz won the fight in under a minute with a slam, so it didn't have time to develop into something special.

8 8. Nam Phan vs. Leonard Garcia at UFC 136

In this highly anticipated rematch at UFC 136, Nam Phan and Leonard Garcia were looking to replicate the outstanding fight they put on in their first meeting inside the cage. It did not disappoint. It was a sloppy slug fest in which both men tried to drag their opponent into deep water. Ultimately, Phan got the victory in the rematch that exceeded all expectations. The main event was the third installment of the Maynard vs. Edgar trilogy, a good fight in its own regard, but can’t stack up to the fun that ensued during the Phan/Garcia fight.

7 7. Roger Huerta vs. Leonard Garcia at UFC 69

Speaking of Garcia, he along with Roger Huerta appears at number 7 on this list thanks to their great fight at UFC 69. The fight was a brilliant back and forth battle that ended with both men embracing and showing true sportsmanship, and Huerta ultimately winning a decision. Now, the main event of this card featured Matt Serra’s historic KO of GSP, but it was Huerta that received the most press on this night, as he became the first MMA fighter to appear on the cover of Sports Illustrated because of his fight.

6 6. Georges St-Pierre vs. B.J. Penn at UFC 58

This was the first match up between UFC superstars B.J. Penn and Georges St-Pierre. Going into this fight, B.J. Penn was the favorite and the former champion, while GSP was the young up and comer from Canada. Penn was looking past GSP towards a rematch with Matt Hughes. Boy, was that a bad idea. This fight was extremely competitive throughout and is to this day one of the best Welterweight fights in history. GSP ultimately won the fight and began his reign as the best Welterweight ever. The main event featured Rich Franklin defending his title vs. David Louiseau in what was a lackluster main event, especially when compared to Penn/GSP.

5 5. Sam Stout vs. Spencer Fisher at UFC 58

Here is another fight at UFC 58 that was far better than the lackluster main event. This was the first of three eventual fights between the two aggressive fighters. Fisher dominated the first round, and the second round was razor thin. But the third round, and the fight, belonged to Stout as he imposed his game plan of control and technique. This fight was the prototypical example of a back and forth war. Though some fans may not enjoy it, this fight has a perfect mix of striking and grappling and was a very technical match up.

4 4. Gilbert Melendez vs. Diego Sanchez at UFC 166

This was a match up from the Gods. This fight was the perfect blend of fighters to create a battle for the ages. This fight is often regarded as the best fight of 2013 and rightfully so. For three straight rounds, both men bit down on their mouthpieces and trudged forward in combat. And even though Melendez walked away the winner, it can be argued that the fans were the real winners. This fight far overshadowed the main event of Cain Velasquez vs. Junior Dos Santos 3, a fight that was utterly dominated by Cain, and was pretty hard to watch.

3 3. Dennis Bermudez vs. Matt Grice at UFC 157

This is a fight that largely flies under the radar, but shouldn’t. The first round of this fight was madness as both men landed several hard shots and both were dazed at different points in the round. The second and third rounds couldn’t continue like this, could they? Oh boy could they ever. The second and third rounds again consisted of back and forth striking and grappling exchanges that eventually led to a decision victory for Dennis Bermudez. The main event of this card featured Ronda Rousey vs. Liz Carmouche, which was a great moment for sure, but after just witnessing the beauty that was Bermudez/Grice, this main event just couldn’t stack up.

2 2. Chris Leben vs. Yoshihiro Akiyama at UFC 116

Chris Leben. The man is synonymous with true grit and a constant will to win. And that will was on full display throughout his fight with Akiyama at UFC 116. The fight was outstanding as both men were like zombies for a large portion of the fight, just going forward relentlessly throwing punches. In an unreal show of heart, Leben locked in a triangle choke with less than 30 seconds left and was able to secure the win by submission. The main event featured Brock Lesnar vs. Shane Carwin. The fight had a great first round, but the fight ended soon after and left the fans yearning for another long, drawn out battle like Akiyama vs Leben.

1 1. Forrest Griffin vs. Stephan Bonnar at the TUF 1 Finale

Yes, this fight was not the main event. Griffin vs. Bonnar is almost unanimously called the best fight in UFC history. This is the fight that thrust the UFC and MMA as a whole into the mainstream as it was 15 minutes of straight back and forth brawling between both men. Both men had their moments and both were on the receiving end of some brutal strikes. The fight ended with Griffin as the victor, but the fight was so good that both men were given six figure deals with the UFC. The main event of this card was Rich Franklin vs. Ken Shamrock, and in no way whatsoever can this fight even come close to the magnitude and importance that Griffin/Bonnar had on MMA history