Conor McGregor Vs Floyd Mayweather
A fight that is simultaneously hugely influential in the current combat sports landscape while somehow still feeling like the events of a fever dream, in 2017 Conor McGregor's long-stated ambitions to conquer the world of boxing would be tested against one of the consensus greatest boxers of all time in Floyd Mayweather.
McGregor came into the bout riding a wave of momentum like the sport of MMA had rarely seen before. After avenging his loss to Nate Diaz in one of the biggest events in the sport's young history, McGregor would do the unthinkable and completely dominate reigning UFC Lightweight Champion Eddie Alvarez to become the first fighter in UFC to simultaneously hold belts in two different weight classes.
Mayweather meanwhile had retired from active competition in September 2015 with a win over Andre Berto seemingly content with his professional record forever standing at 49-0.
The hype for the potential clash spread like wildfire across the media, with speculation rampant on the contest.
Then, it happened.
Standing across a four-sided ring from one of the greatest boxing talents of a generation, McGregor seemed completely unfazed by the sheer scale of the event surrounding him. The Irishman would even enjoy some early success after the bell rang, but Floyd's masterful defence and ring generalship would prove to be too much, with Floyd ultimately finishing the UFC champion in the tenth of twelve scheduled rounds.
Ray Mercer vs Tim Sylvia
The MMA versus boxing argument is often boiled down to the idea that a boxer will defeat an MMA fighter in a boxing match and an MMA fighter would defeat a boxer in an MMA fight.
However, this is not always the case.
Take, for example, Ray Mercer Vs Tim Sylvia back in 2009.
While both men had previously held world heavyweight titles in their respective sports, Sylvia was still considered a top ten heavyweight whereas Mercer, aged 48 and over two decades removed from his Olympic triumph in 1988 was viewed as being well past his fighting prime.
Originally set to take place as a boxing match, Sylvia's limited in-ring experience caused issues with the sanctioning body, and the fight would ultimately instead take place under MMA rules.
At the start of the fight, Sylvia immediately moved forward and landed an inside leg kick. A discontented looking Mercer fired back, landing a devastating right hand that floored the former UFC Heavyweight Champion just nine seconds into the first round.
Mercer would later remark that the pair had made a gentleman's agreement to only box with each other inside the cage, hence his hilarious expression when Sylvia immediately opened up the fight with a decidedly un-pugilistic leg kick.
Anderson Silva Vs Julio Cesar Chavez Jr
Do you know how we said there are exceptions to the boxers in a ring/MMA fighters in a cage rule? Well, it works both ways.
During his legendary run with the UFC, Anderson Silva often expressed a desire to test his skills in the boxing ring, with multi-weight world champion Roy Jones Jr often mooted as a potential opponent for the Spider.
However, despite persistent speculation Silva's transition to the sport of boxing repeatedly failed to materialize. That is, of course, until Silva was released from his contract last year.
In June of this year, the former UFC Middleweight Champion faced former WBC Middleweight Champion Julio Cesar Chavez Jr in an 8 round contest.
Despite having just two previous professional boxing bouts on his record compared to his opponent's 59, Silva genuinely looked like the more seasoned boxer on the night, out striking his opponent and ultimately winning a split decision.
The only downside to Silva's success is the lingering questions of just how successful he could have been in boxing if he had transitioned after losing his UFC title in 2013.
Royce Gracie vs Art Jimmerson
The question of what would happen if two masters of their respective combat disciplines engaged in a no-rules fight had raged for years in martial arts communities. After decades of speculation, the advent of the UFC in 1993 sought to provide a conclusive and definitive answer.
Representing the sport of boxing in the UFC's inaugural one-night tournament was Art Jimmerson, a nationally ranked light-heavyweight boxer with a record of 23 wins and 5 defeats in his professional career.
Jimmerson's background provided an air of legitimacy for the burgeoning UFC, but in his debut fight against Royce Gracie, the limitations of pugilism as a combat art when fighting a skilled grappler quickly became clear.
Unlike Jimmerson, Gracie's experiences of brutal Vale Tudo fights in his native Brazil meant that he was fully aware of what he was getting himself into, and the disparity in preparation soon became apparent in the Octagon.
A former Golden Gloves winner, Jimmerson was worried he would damage his hands and potentially jeopardise his boxing career in a bare-knuckle fight, elected to wear a single boxing glove during the contest. Predictably his equipment selection only hastened his defeat, and he submitted after being mounted by Gracie in the first round of the fight.
James Toney vs Randy Couture
Much like Connor McGregor nearly a decade later, three-weight boxing world champion in 2010 James Toney began using all of his media opportunities to build hype for an improbable, boxing vs MMA fight in the UFC.
However, despite remarking that he was a fan of the boxer, Dana White would not exactly be charitable in choosing an opponent for Toney's Octagon debut.
Less than six months after the promotion announced that Toney had signed to embark on a career inside the cage, White announced that his debut opponent would be former UFC Heavyweight and Light Heavyweight Champion Randy Couture.
In the lead up to the fight at UFC 118, Toney assured reporters that he had done his due diligence on the sport of MMA and had been working on his grappling skills.
However, Toney's training would ultimately prove to be no match for Couture's near lifetime of experience when the pair finally met in the Octagon.
Unwilling to even entertain Toney's one shot at success, Couture immediately took the boxer down, and began working towards a submission. Toney floundered desperately but the outcome was an inevitability with Couture eventually securing an arm-triangle choke and forcing Toney to tap out in the first round.
Long-suffering Hull City fan, combat sports history aficionado and world renowned champion of the church of Chael Sonnen.