The Ultimate Fighting Championship is supposedly the top mixed martial arts organization in the world today and a promotion that, theoretically, should feature the best male and female fighters on the planet. As those who are passionate fans of the sport know, however, the UFC has showcased fighters who never should have stepped foot in the Octagon for an exhibition, let alone for a real battle, throughout its history. In some cases, the UFC merely needed bodies for shows during the early years of its existence or for television programs meant to hype better fighters. Then, there were the times the UFC booked fights only because one of two of the fighters involved in the contest were recognizable names to casual would-be customers who otherwise would have ignored a certain Pay-Per-View event.

It probably isn't a surprise to any knowledgeable person that two of the worst UFC fighters who never should have stepped foot in the Octagon were, in reality, not respected MMA combatants. One is a former World Wrestling Entertainment Superstar who was signed by the UFC because of his name alone, and that person probably should not have been allowed to have a spot on any Pay-Per-View program. Another is a boxer who was thoroughly humiliated when he stepped foot in the Octagon during a UFC show. The hope, in the future, is that the UFC will be better about the individuals the promotion allows to fight, although the company will likely understandably always put smart business decisions ahead of doing what is right for the sport.

15 15. Joe Son

We begin the list with Joe Son for multiple reasons. For starters, he played the role of Random Task in the movie Austin Powers: International Man of Mystery. Son also happens to be one of two fighters mentioned in this piece who suffered defeats to Keith Hackney in the UFC.

That loss was his only UFC fight, and Son failed to register a single win during his four-fight pro career. Son's name was in the news once again in September 2011 after he was sentenced to life in prison for his alleged involvement in a gang rape that occurred on Christmas Eve back in 1990. He was later accused of killing his cellmate behind bars, although he managed to avoid the death penalty in that case.

14 14. Rolles Gracie Jr.

You couldn't be blamed for being surprised to see the Gracie name on a list of fighters who never should have stepped foot in the Octagon. Sometimes, the apple, sadly, falls far from the tree. Rolles Gracie Jr. was unable to live up to the expectations that come with having such a legendary last name, as he lost to Joey Beltran via TKO at UFC 109.

Renzo Gracie, his cousin, stated after the fight Rolles tired himself out versus Beltran, in part, because of the pressure he felt heading into the contest. Those making important decisions for the UFC obviously weren't convinced, as he was released by the promotion following that single defeat. He failed to become a true star away from the UFC, a sign the company made the right call.

13 13. Jason “Mayhem” Miller

Jason “Mayhem” Miller deserves credit for making a name, not to mention money, for himself via his unique personality and his involvement with the MTV program Bully Beatdown. Miller was more of a television host than a true UFC fighter, however, even though he did manage to earn an impressive record for himself when fighting outside of the company.

He failed to pick up a single win during multiple stints with the UFC, and he was unceremoniously fired from the promotion by Dana White following an alleged incident that reportedly occurred after he lost to C.B. Dollaway at UFC 146. Miller was entertaining, and maybe also a headache, at times, but he never really deserved a spot in the UFC even at the height of his popularity.

12 12. Seth Petruzelli

Seth Petruzelli was somewhat unlucky in that he became famous among casual fans and viewers when he dismantled Kimbo Slice at an EliteXC show in October 2008 so easily some assumed there had to be some behind-the-scenes shenanigans involved in the contest's outcome. It turns out Petruzelli was that much better than Slice but still not good enough to hang in the UFC. He already had a pair of losses on his UFC resume when the promotion gave him a second chance leading up to UFC 116, but the company moved on from Petruzelli after he suffered two more losses.

His career now serves as proof that the quality of fighters in smaller promotions not associated with the UFC is unquestionably worse than what you'll see in the top fighting organization in the world.

11 11. Art Jimmerson

You may not immediately be familiar with the name Art Jimmerson, but odds are you have seen either pictures or video highlights of his lone UFC encounter. Jimmerson, a boxer, famously wore a single boxing glove for his fight versus Royce Gracie at UFC 1, a decision that did not help his cause for the couple of minutes that he lasted before he was finished off by Gracie.

The idea, at the time, was that the UFC was a “no rules” organization meant to feature talented fighters from different practices and even different sports. Obviously, Jimmerson was badly over-matched for this fateful fight, but he still has a legacy in the sport's history. Is it better to be merely remembered but not necessarily respected as a talented UFC fighter?

10 10. Jack May

On paper, Jack May has the goods to become a star in the Heavyweight Division of a promotion. Per Sherdog, he checks in at 6-foot-8, and he could have knockout power if he were able to develop his strikes to the point where he could land shots against top-tier talents. The problem here is that May quickly flamed out of the UFC after only a pair of losses.

May failed to impress during a knockout loss to Derrick Lewis at UFC on FOX 11, and he was beaten by Shawn Jordan at UFC Fight Night 47. The UFC believed they'd seen enough and cut May after his second loss in the promotion, and the 36-year-old is now trying to reestablish himself with Bellator. Perhaps he will silence critics en route to returning to the UFC in the future.

9 9. Yoji Anjo

CM Punk was hardly the first pro wrestler to learn that making the transition to life in the UFC from a career inside the ring can be rather difficult. Yoji Anjo was an accomplished pro wrestler who had worked in Japan when the UFC gave him a chance to compete at the Ultimate Japan show that occurred in December 1997. Anjo lost to David “Tank” Abbott at the event, which is somewhat ironic because Abbott eventually joined up with World Championship Wrestling before the end of the decade.

That defeat was not a one-off for Anjo, as he lost two other encounters while competing underneath the UFC umbrella. His overall official fighting record, per Sherdog, is 0-5-1, and the last recognized fight of his MMA career was a loss to Ryan Gracie that occurred in December 2004.

8 8. Ruan Potts

In recent memory, the UFC has failed to build a Heavyweight Division filled with a wide depth of talented competitors. Ruan Potts began his career with wins in eight of his first nine fights, but it did not take long to learn the fighters he faced in Africa were not at the level of those worthy of earning UFC contracts.

Potts failed to make it to the end of all three of his UFC encounters, all of which he lost after he was unable to fully protect himself from strikes. The promotion released him in April 2015, and Potts, now 39 years old, probably won't earn himself another opportunity to compete in the UFC before he calls time on his fighting career. Perhaps things could've gone better for him had he entered the UFC a decade ago.

7 7. Gabe Ruediger

Those of you out there trying to remember why the name Gabe Ruediger seems familiar need only think back to what occurred during The Ultimate Fighter Season 5. Ruediger, who had one UFC fight under his belt at the time, thought it wise to eat ice cream cake leading up to his first fight of the season, a decision that resulted in him missing weight and ultimately being booted from the show by UFC boss Dana White.

For whatever reasons, though, the UFC elected to bring Ruediger back, mostly to lose to Joe Lauzon in the first round of a contest that occurred at UFC 118. An unimpressive loss to Paul Taylor at UFC 126 would prove to be the end of his time with the company, and he retired in the spring of 2013.

6 6. John Alessio

John Alessio has gone by the nickname “The Natural” during his fighting career, but he proved to be anything but a natural during multiple stints in the UFC. Alessio lost his debut encounter in the promotion back in June 2000, he suffered a pair of defeats in 2006 and he was released from the UFC after he lost two additional fights in 2012.

To his credit, Alessio has found success in smaller promotions many out there don't know exist during a career that has largely gone under the radar, but he will turn 38 years old in the summer of 2017. It's safe to assume the promotion won't give him another chance, meaning he'll forever hold one of the worst overall records in UFC history (0-5).

5 5. Sean Gannon

It's another example of the UFC signing a guy because he earned himself a name among some Internet users for beating Kimbo Slice. After Sean Gannon defeated Slice in an unsanctioned brawl, the UFC put pen to paper on a contract with the Boston Police Department officer hoping he could bring some publicity to the company.

While Slice was at least a draw who attracted interest from people who recognized his name and also from fight fans who wanted to see if he was the real deal or a joke, Gannon was a one-and-done UFC competitor. His loss to Branden Lee Hinkle at UFC 55 proved to be the last official fight of his career. Luckily for his health and for those who enjoy following the promotion, Gannon hasn't since stepped foot in the Octagon.

4 4. Emanuel Yarbrough

Dedicated fight fans who have followed the UFC since the company's first Pay-Per-View shows probably remember Emanuel Yarbrough as the former sumo wrestler who lost to the much smaller Keith Hackney at UFC 3. The promotion, simply put, needed bodies and guys willing to compete in a sport many honestly didn't fully understand in September 1994.

Even back then, the UFC realized a would-be competitor such as Yarbrough had no business stepping foot in the Octagon more than once, as he never again fought for the promotion. While highlights of Hackney taking Yarbrough out made for interesting footage for individuals who never saw any MMA action, there is zero chance such an unskilled and out-of-shape fighter would get even a look from any respectable promotion in today's world.

3 3. Kimbo Slice

Even when Kimbo Slice managed to notch a victory over Houston Alexander at The Ultimate Fighter 10 Finale, it was pretty clear the man who made his name as a famous street brawler featured in YouTube videos lacked the skills needed to compete with some of the top fighters in the world and in the UFC. Slice's second official UFC fight occurred at UFC 113 when he faced off with Matt Mitrione, but that contest, like the majority of Slice's MMA career, was more hype than substance. Mitrione defeated Slice in the second round via TKO, and the UFC quickly and wisely decided to move on from the Slice experiment.

Looking back, it's actually somewhat amazing, not to mention a bit horrifying, UFC match-makers dared to put Slice on any Pay-Per-View card.

2 2. CM Punk

You have to give former WWE Champion CM Punk credit for being willing to take a risk, leave his pro wrestling career behind and attempt to make it in the UFC after he signed with the company in late 2014.

The harsh reality with Punk is that he was never even close to being ready to fight any UFC competitor, even one with as lackluster a resume as the one owned by Mickey Gall in September 2016. The fight between Punk and Gall at UFC 203 was nearly painful to watch, as Punk was essentially a sparring partner until Gall finished the encounter with a rear naked choke in the first round. Punk hasn't fought in the UFC since, and it seems that his career with the company has ended before it ever really began.

1 1. James Toney

The UFC was a different promotion still struggling for acceptance among casual sports fans when the organization gave boxer James Toney an opportunity to fight Randy Couture at UFC 118. This proved to be a delightful encounter for MMA fans wanting to see the boxer get humbled inside of the Octagon, as Couture dominated the match en route to winning via submission before the halfway point of the opening round.

While this booking decision generated plenty of international headlines for the UFC, the fact remains Toney never should have been allowed to step foot into the Octagon, and the company is lucky Couture wasn't looking to injure his opponent on this night. Go back and watch these couple of minutes of “action” if you still believe Floyd Mayweather should ever fight in the UFC.