The majority of the time in combat sports, there are rules and regulations to ensure that competitors are evenly matched.Unfortunately for some of the names on this list, there are times when mismatched fights slip through the cracks.Mismatched bouts can arise for a wide variety of reasons. Crossover events, in particular, are notorious for putting fighters in dangerous situations where they can end up facing an opponent far more skilled in a style of fighting they aren't familiar with.Even when opponents are fighting in the discipline in which they've both trained, and using weight classes, it doesn't always stop fights arising between opponents of completely different skill levels.These are some of the biggest mismatches in the history of combat sports.
Floyd Mayweather vs Tenshin Nasukawa (Boxing)
Floyd Mayweather has never been afraid to step out of his comfort zone. Since the American retired from professional boxing, he has taken part in some absurd events.
From boxing UFC star Conor McGregor to social media personality Logan Paul, Mayweather is no stranger to an exhibition or even a crossover.
But this event, especially, stands out as a ridiculous mismatch of skill levels. The former world champion was offered big money for a crossover bout in Japan against undefeated kickboxing champion Tenshin Nasukawa.
While an undefeated kickboxing champion may not seem like a ridiculous mismatch, Tenshin quickly found out that not being allowed to use his legs put him at a significant disadvantage when compared to a champion boxer.
Mayweather incredibly floored Tenshin three times in the opening round before his corner threw in the towel after just 136 seconds.
Mayweather vs Logan Paul (Boxing)
At the time of the fight, Logan Paul was roughly 35lb heavier than Mayweather and had a 6-inch height advantage.
However, even with the sheer difference in size, it's obvious to most that the skill levels of the two fighters were a complete mismatch.
Mayweather entered the fight with an official record of 50 wins and 0 losses. A stark contrast to Logan Paul's one professional bout against fellow Youtuber KSI, which the American lost.
Surprisingly, however, Paul somehow managed to go the full distance against the former world champion. But many pundits and fans alike felt that Mayweather took it easy on Paul, and was only interested in the fight for financial gain as the boxing star had nothing to prove.
Randy Couture vs James Toney
Despite a small number of events happening in recent years, the UFC generally avoids crossover bouts.
But at the UFC 118 event, ex-professional boxing champion James Toney took to the octagon to face off against UFC veteran Randy Couture.
By this time Couture had already beaten the likes of Tito Ortiz, Vitor Belfort and Chuck Liddell. So of course, it was unsurprising when Couture took Toney straight to the mat and secured the victory using an arm triangle just three minutes and 19 seconds into the first round.
Butterbean vs Bart Gunn (WWE/Boxing)
Out of all the crazy events the WWE have thought up over the years, this certainly has to be one of the worst.
Eight WWE fighters were pitted against each other in real boxing matches during the Brawl for All concept. While that may not seem like such a bad idea, the prize awarded to the winner clearly was.
Bart Gunn, real name Michael Polchlopek, was victorious amongst the WWE competitors, and his prize was a Wrestlemania boxing bout against the notorious 375lb knockout artist Butterbean.
As expected, Butterbean knocked the wrestler out cold in under a minute.
Mirko Cro Cop vs Dos Caras Jr (MMA)
Mirko Cro Cop is a fighter that most veterans wouldn't take lightly, but Dos Caras Jr took on the Croatian after just five professional fights, two of which he had lost.
Cro Cop entered the bout with a professional MMA record of 7-0-2, undefeated in his first nine fights with two draws.
Caras Jr was stunned by a head-kick from Cro Cop just 46 seconds into the first round and the fight was immediately ended.
Around a decade later Caras Jr appeared in WWE sporting the ring name Alberto Del Rio. Luckily for the Mexican-American, his career in professional wrestling was much more successful than his bout against Cro Cop.
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CM Punk vs Mickey Gall (UFC)
CM Punk was a legend in the world of professional wrestling before a fallout with Vince McMahon saw the icon turn to the UFC.
After two years of training MMA Punk, believing he was ready, was scheduled to fight Mickey Gall.
Gall completely dismantled Punk before submitting the ex-wrestler in just two minutes and 14 seconds. Punk waited almost another two years to step back into the octagon but this time lost via unanimous decision.
Although the fight went down in history as a no-contest after his opponent, Mike Jackson, tested positive for Marijuana.
Miranda Adkins vs Seniesa Estrada (Boxing)
28-year-old boxer Seniesa Estrada entered this bout with a professional record of 18-0, but somehow, in a ridiculously poorly planned turn of events, was allowed to face off against a 43-year-old whose 5-0 record was achieved only at a local level.
Adkins looked out of her depth from the second the bell rang with apparently no idea how to defend herself from the quick combinations of Estrada.
Adkins was left flat on her back in just 7 seconds, becoming one of the fastest knockouts in women's boxing history.
Yuji Nagata vs Fedor Emelianenko (MMA)
Yuji Nagata was another professional wrestler who attempted to step into the very real world of MMA.
Nagata worked for New Japan Pro Wrestling but was convinced by Antonio Inoki to take part in the crossover bout. Amazingly, this wasn't the first time Inoki had convinced Nagata to fight a professional, Nagata had previously taken part in an event against Mirko Cro Cop.
Despite being brutalised by Mirko, Nagata astonishingly agreed to fight Emelianenko. Unsurprisingly, Nagata was TKO'd by the Russian in just over one minute.
Emmanuel Yarbrough vs Daiju Takase (Kickboxing)
In one of the biggest weight discrepancies of all time, 600lb UFC veteran Emmanuel Yarbrough took on 160lb MMA fighter Daiju Takase.
At the time Yarbrough had one MMA victory under his belt, however, the fighter hadn't achieved his victory through skill but had simply used his enormous weight to smother his opponent.
Takase entered the bout with no professional fights but was trained in multiple martial arts. Despite the size difference and Yarbrough once again attempting to smother his opponent, Takase miraculously won the bout after unloading a flurry of punches after getting himself off the ground.
Bob Sapp vs Kiyoshi Tamura
Another bout was held in Japan, the event between Sapp and Tamura was marketed as a strength vs skill contest.
Bob Sapp was a former NFL player, turned MMA fighter. Sapp was a 6'4 man mountain, whereas his opponent Tamura, was 5'9 and only weighed around 180lbs.
Tamura believed though, that his background as a kickboxing veteran and his distinct speed advantage would see him prevail.
However, that belief probably disappeared very quickly as the kickboxer was savaged by Sapp in just 11 seconds.
Katie Castro vs Ilima-Lei Macfarlane (MMA)
Katie Castro was inspired to take up MMA after watching Ronda Rousey's UFC performances.
It became apparent quite quickly that Castro had no idea what she was doing as she arrived in the Octagon wearing a full gym outfit, including leggings and a long-sleeved top.
Despite this also being Macfarlane's first professional MMA bout, the skill gap was instantly painfully obvious. The fight lasted only 10 seconds before Castro lost by technical knockout.