MMA is a sport that instantly demands respect for its combatants inside of it. Whether that is inside of the UFC, Bellator, ONE Championship, or any MMA promotion, it's hard not to garner an insane amount of respect for the bravery that is seen by fighters. They are quite literally going in to fight another grown human being, in their underwear, in front of millions of people.

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However, there are fights that while rare, do occur where it's hard to look at the fighters in a good light. Such fights end up embarrassing both fighters involved and oftentimes the fans as well.

10 Kimbo Slice vs. Ken Shamrock

Ken Shamrock Bellator 149

Kimbo Slice vs. Ken Shamrock was a bout that was originally supposed to occur under the EliteXC banner in fall 2008. However, on the day of the fight, Shamrock was forced to pull out as a result of injury. At the time, the bout was seen as a squash match for the rising superstar Slice, as he was expected to batter Shamrock who was seen as years out of his prime.

Seven years later, Shamrock and Slice were both years from their best. Shamrock was especially ancient as he fought at Bellator 138 at the age of 51. The fight was bad, both men looked in slow-motion as Slice garnered a first-round knockout.

9 CM Punk vs. Mike Jackson

CM Punk UFC 225
Kamil Krzaczynski-USA TODAY Sports

CM Punk's second UFC fight wasn't a pretty one. His first UFC fight was a shellacking from young prospect Mickey Gall, his second fight was against fellow 0-1 MMA fighter Mike Jackson. However, that 0-1 record is a bit deceiving, given Jackson's background as a boxer where he is 4-0.

The fight was terrible. Punk ruthlessly shot for takedowns to no avail, got gassed quickly, and it seemed like Jackson decided to just take the fight as target practice as a result of Punk's incompetence. In a weird twist, despite initially losing the bout via decision, the result was overturned years later due to a positive drug test by Jackson.

8 Royce Gracie vs. Ken Shamrock 3

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Another Bellator fight that happened years beyond its expiration date was Royce Gracie vs. Ken Shamrock 3. Both men were either already past or nearing the age of 50 when they decided to throw down at Bellator 149.

The bout was heavily criticized heading in and was even worse than imagined. Both men looked their age, did nothing for a few minutes, got into a quick clinch where Gracie knee'd Shamrock in the groin and got the TKO finish after Shamrock collapsed and the referee didn't see the low blow. Showing once again why middle-aged men probably shouldn't be fighting.

7 Mark Hunt vs. Justin Willis

Mark Hunt UFC Adelaide
James Elsby-USA TODAY Sports

Mark Hunt's swansong in the UFC wasn't what fans expected. Rather than fighting another legend or top-ranked fighter, he was matched up with the lowly-revered Justin 'Big Pretty' Willis for Hunt's final fight in Australia. If fans were disappointed in this fight heading in, they felt worse heading out.

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Nothing really happened over the 15 minutes that the two heavyweights were in the cage. Hunt looked dejected knowing that his last fight was a dud, Willis felt disappointed he didn't get a better showcase win, and fans forgot the fight happened two hours after the fight ended.

6 Frank Mir vs. Mirko Cro Cop

Frank Mir UFC 146
Ron Chenoy-USA TODAY Sports

UFC 119's main event between Frank Mir and Mirko Cro Cop seemed like a dream fight on paper. A former UFC heavyweight champion taking on a PRIDE legend had all the makings of a classic and instead went down as one of the worst fights ever.

The fight had nothing happen all the way up until the final minute, where Mir got a knockout with a knee in the final moments of the fight. The fight was so bad that Mir didn't even get a 'Knockout of the Night' bonus despite being the only knockout on the card. It was a bad look for both men that night.

5 Tim Sylvia vs. Andrei Arlovski 3

Tim Sylvia UFC

Tim Sylvia and Andrei Arlovski's trilogy fight at UFC 61 is one of the most disappointing fights in UFC history. While not a bad fight per se, both men went into the bout having scored massive first-round finishes over the other heading in.

Rather than go for it, the two men decided to point-fight. As a result, we got a boring, slow bout where Sylvia won a unanimous decision. The fight was embarrassing for both men and is seen as the worst moment for the UFC's heavyweight division.

4 Gabi Garcia vs. Yumiko Hotta

Gabi Garcia in training

Most of Gabi Garcia's fights are somewhat embarrassing, but there's none worse than Yumiko Hotta. In 2016, RIZIN decided to put on a bout between the 30-year-old, 207-pound Garcia and the 49-year-old, 165-pound Hotta. And yes, it went exactly as expected.

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Hotta got dominated and finished almost immediately. Garcia felt embarrassed for the bout and didn't even celebrate, and the bout just felt completely uncomfortable.

3 Derrick Lewis vs. Francis Ngannou

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Stephen R. Sylvanie-USA TODAY Sports

Derrick Lewis vs. Francis Ngannou was one of the most anticipated fights of 2018. The co-main of UFC 226, it was a battle between the two heaviest hitters in the UFC at the time, and arguably two of the heaviest hitters ever in the promotion. Instead, we got one of the worst fights ever.

Both men didn't do much of anything. Lewis won a decision because someone had to, and the fight lives in MMA lore as the most disappointing and embarrassing fight ever.

2 Anderson Silva vs. Thales Leites

Anderson Silva
© Ed Mulholland-USA TODAY Sports

It's easy to forget, but there was a decent-sized history of time for Anderson Silva where he was putting on disappointing fights. The worst of those fights occurred at UFC 97, where Silva faced off against Brazilian jiu-jitsu ace Thales Leites.

Silva spent the vast majority of the bout taunting, avoiding confrontation, and slapping Leites. Leites, for his part, failed to push the pace either, as he lost a wide decision. The fight resulted in Dana White publically blasting Silva as a result and it's hard to blame him.

1 Kimbo Slice vs. Dada 5000

Bellator 149's co-main event between Kimbo Slice and Dada 5000 is the most embarrassing fight ever for both men. It seemed that the fight was going to be a slugfest between two knockout artists going in, and instead was a fight that saw more laughter than anything.

Both men were gassed almost immediately. Neither did much of anything at all, and the fight ended in the third round as Mr. 5000 collapsed from exhaustion and lost via TKO. Slice's post-fight interview was barely legible due to him being so out of breath, it was like a fight scene in a comedy movie, it was so bad.