Combat sports can draw on human emotion like no other sports can - the risks and rewards involved are so much more primal, the dangers so much more real, they truly offer the highest of highs and the lowest of lows.
Recently we looked at some of those highs in detail, but what about the lows?
Though Fight Island has certainly kept us entertained for the last few weeks, it has also reminded us of how depressing the sport can be.
At UFC 251, for the better part of 15-minutes former featherweight king Jose Aldo went back to his roots and showed that he was more than capable of not only holding his own against the current top talent, but even of beating them, only for his cardio to fail him and subsequently derail his bantamweight title hopes as Petr Yan poured on the pressure late.
The loss wouldn't have been so bad if it weren't for the horrific judgement shown by referee Leon Roberts, who in the fifth round, let Aldo take upwards of one hundred unanswered strikes as Aldo's busted open face spewed blood on the canvas while he knelt helplessly on the floor, crippled by exhaustion as his corner and the referee stood idly by and watched him take unneccessary punishment.
Last weekend we witnessed longtime fan favourite Joseph Benavidez take one of the most vicious one-round beatings in MMA history in what was to be his last attempt at a UFC title.
The Team Alpha Male standout has been the perennial top contender, first in bantamweight then at his true home of flyweight since the division was introduced in 2012, never dropping below the top three in the rankings and only ever losing to champions Dominick Cruz and Demetrious Johnson (save for an extremely controversial loss to Sergio Pettis).
Despite holding a win over Henry Cejudo, Benavidez never got a shot at Cejudo's title as the former champion opted to fight a descending bantamweight and then move up in weight classes - instead, he finally earned his third crack at UFC gold opposite Deiveson Figueiredo earlier this year for the vacant strap.
The fight was shrouded in controversy as Figueiredo missed weight, then an accidental headbutt in the second round that went unnoticed by the referee led to a knockout loss for Benavidez - with Figueiredo inelligible to win the title because he missed weight and the controversy surrounding the finish, Benavidez was given a shot at redemption last Saturday.
Most expected the fight to go Figueiredo's way, especially given that he was in better shape and made weight this time, but few expected the extremely vicious way in which Benavidez would lose.
Figueiredo dropped Benavidez not once, not twice, but three times in the opening round, securing two tight rear-naked chokes to try and finish the tough vet that Benavidez somehow managed to survive. After the third knockdown and another locked-in rear-naked choke, Benavidez was finally finished and went unconscious as the iron-willed contender refused to tap.
If those brutal bouts aren't enough to get you feeling depressed, don't worry, we've got you covered - here are 15 of the saddest moments in MMA history.
Note: this list is purely speaking about in-cage moments and as such does not include things such as deaths, illnesses, injuries, etc. that occurred outside of competition.
15. Urijah Faber getting demolished by Petr Yan
The first entry on this list comes at the expense of Joseph Benavidez's mentor, Urijah Faber.
Fans of the "California Kid" considered themselves lucky when the longtime fan favourite announced his retirement in 2016 - while seeing a legend in the sport hang up their gloves is always bittersweet, unlike most fighters Urijah Faber had chosen to finish his illustrious career before he had sustained the excessive damage and string of knockout losses most of his peers suffer in their waning years.
Though his retirement fight showed he was still more than capable of putting on a show and competing with solid competition, Faber had clearly declined in recent years and simply wasn't the perennial contender he once was - despite this, he had still managed to avoid taking excessive punishment while competing against top flight competition and his only finish loss in the last eight years had been a highly controversial early stoppage against Renan Barao.
Faber had unsurprisingly remained in the gym throughout his retirement and teased that he could return for the "right fight", but that idea seemed to fizzle out as time went on - until 2019.
Out of nowhere Urijah announced that he was coming out of retirement to make another title run, accepting a fight with the vastly younger prospect Ricky Simon.
Reaction to the news was rather mixed - many thought the 40-year-old would simply not be able to compete with the extremely strong and athletic Simon, though savvy fight fans knew Simon's rather lacking (at the time) striking skills and porous defense offered a clear path to victory for Faber even at his advanced age, especially given that power tends to be the last thing to go in an aging fighter.
Faber would ignite his hometown Sacramento crowd by smashing the highly touted prospect in just 46 seconds, announcing to the stacked bantamweight division that the California Kid wasn't done terrorizing them just yet.
The thrilling victory certainly made for a good story, but some were fooled into thinking that Faber would be able to still compete with the top contenders in the shark tank that is the 135-pound division.
In truth, even at 40 Faber is still more than capable of beating most bantamweight fighters on the planet - earlier in his career however he would often come up short against the truly elite in the division, and even though he hadn't accrued a huge amount of damage in his career, his ability to absorb punishment had understandably diminished with age and that would spell disaster against a truly top-tier opponent at this stage in his career, especially as his reflexes and speed continued to decline.
Regardless, Faber's win and name value earned him a top contender and a title shot should he win - the only problem was that he'd have to go through an absolute killer in Petr Yan to do it.
Even fans that had picked Faber to beat Ricky Simon dreaded this fight when the time came for the two to enter the Octagon.
Petr Yan was a 13-1 powerhouse with a strong grappling background, slick boxing and heavy hands combined with a relentless pace and iron chin. Although Faber would certainly have an experience advantage, Yan had cut his teeth fighting extremely talented competition in Russia and had defeated all five of his UFC opponents, including vets like John Dodson and top ten staple Jimmie Rivera.
The 26-year-old Russian would not only sport a youth advantage, but his style would have made him an extremely tough matchup for Urijah even in his prime - at 40 years of age, Faber would need a miracle just to survive let alone win against someone like Yan.
Faber started off well when the two locked horns at UFC 245 late last year, his trademark speed still holding up all these years later (at least for the opening minutes). Faber scored with strikes of his own and managed to avoid damage for the most part, with some even scoring the competitive round in Faber's favour.
Yan however is known to be a slow starter - he's a textbook swarmer, a striker that relentlessly walks down his prey and continues to open up more and more as a fight goes on, wearing down his victims with vicious combinations until they break.
The second round was what all of Urijah's fans had feared - and then some.
Yan began to find his range, smashing Faber with brutal combinations and savage knees as Faber looked to change levels. Urijah would get dropped twice in the middle frame, showing off his remarkable toughness and fighting spirit by somehow managing to survive the hellacious onslaught.
It was a brutal beatdown and while Faber got through the round by the skin of his teeth, the writing was on the wall.
Years ago, the supremely conditioned Faber would have had a chance to mount a come back in the third round after recovering on his stool; at his age however, no matter how well conditioned an athlete is one simply cannot recover from that kind of punishment in such a short amount of time.
Of course, Urijah would never back down or give up and so he opted to go out on his shield. Less than a minute into the final stanza, Yan attempted a knee as Faber backed out of the clinch; realizing the knee would come up short, Yan instead flicked out his leg and turned it into a kick, catching Faber with his foot and putting the legend down for the third and final time.
The brutal knockout may not have been unexpected, but it was nonetheless heartbreaking for MMA fans around the world.
Faber had seemingly spared his fans from seeing him take unneccessary damage and retired at the right time, only to fall into the same trap that befalls almost every fighter in combat sports just a few years later.
He took more punishment in less than eleven minutes against Yan than he had in most of his career combined. In fact, in his entire WEC/UFC career (which spanned over a decade and 29 fights), Faber had been knocked down just four times, yet he was knocked down three times in the span of about six minutes at UFC 245.
It was a sad reminder that age catches up to every fighter and that sometimes, toughness and heart just earns you a worse beating.
14. Chris Weidman getting slaughtered in New York
A New York native who had been a prominent supporter of the UFC's efforts to legalize the sport in the holdout state of New York, it was hardly a surprise that the former champion would earn himself a high-profile fight in the UFC's first-ever trip to the famous Madison Square Garden Arena.
After an injury forced him to pull out of an instant rematch with Luke Rockhold for the middleweight title he had just lost, Weidman would look to bounce back from his first career loss by taking on fellow top contender Yoel Romero at UFC 205.
The 11-1 Cuban Olympic silver medalist was riding a seven fight winning streak inside the Octagon with five brutal knockouts to his credit. The contendership bout was one of the most highly anticipated fights on the historic card, an event which featured a whopping three title fights.
The fight was going according to plan through the first two rounds - after a strong start from the explosive 40-year-old that secured him the opening stanza, Weidman outworked Romero in the middle frame and sought a similar result in the third which would secure him the workmanlike victory and return his shot at the title.
And then a Cuban missile sucked the air out of the building.
Just seconds into the third round, Romero perfectly timed a flying knee with a double leg attempt from the former champ, a single moment of explosive perfection demolishing Weidman's dreams of attaining victory in front of his home crowd.
Weidman's face brutally smacked into his own knee as he collapsed to the canvas, a few follow up shots just adding to the viciousness of the knockout before the referee had a chance to step in.
As Romero ran around the Octagon to celebrate, the stunned crowd watched while a dazed Weidman sat up, a gash on the side of his head covering his face in blood.
Weidman wasn't the first nor the last man to lose in front of his home crowd, but to see a former champion who had waited so long and fought so hard to get to fight at home and finally had the opportunity to do so, only to lose in such brutal fashion, was certainly a harsh pill to swallow for the once dominant champion.
Even those that weren't Chris Weidman fans couldn't help but feel sorry for the former middleweight king.
His woes in his home state would continue to haunt him as Weidman would go just 1-2 in his three other fights in New York, including a similarly brutal third round knockout loss to Jacare Souza two years later in a fight he was winning.
13. Frankie Edgar getting stopped for the first time
Frankie Edgar is one of the most beloved MMA fighters on the planet and is sometimes referred to affectionately by fans as the "little engine that could".
Always undersized, the natural bantamweight captured the UFC lightweight title after fighting Gray Maynard to a draw in an epic five round war in which Edgar took a disgusting amount of punishment early yet somehow managed to survive and come back to win the latter rounds. He did virtually the exact same thing in an instant rematch but managed to finish his rival in the fourth round with a flurry of punches to avoid another close decision.
After two razor-thin decision losses, Edgar would finally drop down to featherweight (where he was still undersized compared to most of his opposition) and posted an impressive 7-2 record with his only losses coming in decisions to pound-for-pound great Jose Aldo.
The tough New Jersey native would get another crack at the featherweight title after Max Holloway dethroned Jose Aldo in 2017, but an injury put Edgar's shot on hold and instead Max defeated Jose Aldo once again as the former champ stepped up to fill in for Edgar.
Edgar's fight with Holloway would be rescheduled for March 2018, only for Holloway to pull out due to injury a month before the bout - rather than sitting out and waiting for the champion, Frankie followed in Holloway's footsteps and opted to stay active, instead taking on surging prospect Brian Ortega.
A Brazilian jiu-jitsu ace with a penchant for epic comebacks of his own, Ortega's matchup with Edgar thrilled the MMA community and fans expected a back and forth war.
When the two stepped into the cage at UFC 222 however, it quickly became the Brian Ortega show.
Though he carried power and incredible durability, Ortega's striking had largely been rather lackluster in his prior UFC bouts - his eye for openings and timing had proven to be excellent, but his sloppiness and porous defense had most believing Edgar would hold a notable advantage on the feet.
Showcasing vastly improved boxing, Ortega's slick jab, head movement, and size advantage gave Edgar fits early as the savvy vet struggled to get inside on his younger opponent. Edgar's rushes to try and get inside Ortega's reach were soon met with nasty, sharp elbows that rocked the former lightweight king.
A right hook off of a blocked high kick put Edgar on wobbly legs and forced him to desperately try to tie up his aggressor, only to walk right into an uppercut from the pits of hell. Edgar was floored and stopped by strikes for the first time in his 28-fight career.
It was a brutal and devastating loss for the fan favourite, made all the worse by the fact that Edgar shouldn't have taken the fight in the first place - had he simply waited for Holloway to recover from his injury, he'd have fought for the title (a fleeting opportunity for a fighter in a lower weight class at 36 years old); instead, he risked his spot to take on a hungry young challenger and ended up getting viciously knocked out for his trouble.
It served as proof once again that nothing is guaranteed in this sport and sometimes the "safer" option really is better.
12. Kazushi Sakuraba getting demolished by Wanderlei Silva...for the third time
Japanese MMA legend Kazushi Sakuraba could easily have more than one entry on this list - he was a fighter known for his courage and heart just as much as his cunning and skill, a man with the frame of a small middleweight that regularly took on heavyweights and refused to back down to anyone.
As a result, Sakuraba's very impressive early career in PRIDE quickly became one that saw him taking ridiculous amounts of punishment from more powerful strikers when the grappling ace failed to get the fight to the mat.
Coming into PRIDE's 2003 Middleweight (light heavyweight by North American standards) Grand Prix, Sakuraba was just 2-4 in his last six outings; though he did sport a submission victory over Quinton Rampage Jackson, he had been beaten down by Mirko Cro Cop and most recently by the unknown Nino Schembri, in addition to having been stopped twice by one Wanderlei Silva.
When Sakuraba first found himself in the ring opposite Wanderlei Silva, it was in one of the most highly anticipated fights of 2001; although he managed to drop Silva early, Wanderlei proved to be too much for the Japanese star as the Brazilian knocked him out in just 98 seconds.
Their second meeting would come that same year for the PRIDE middleweight title and offered fans the more competitive battle they had anticipated the first time. Sakuraba did well on the mat early and even got Wanderlei in a tight guillotine choke, which Wanderlei countered by slamming his rival to the canvas and breaking his collar bone in the process.
Sakuraba was able to survive the rest of the 10-minute first round despite the injury, but his corner smartly threw in the towel between rounds to avoid any further damage.
Though a third meeting between the two would have been warranted at the time, the idea quickly turned sour as Sakuraba lost two of his next three fights in lopsided fashion, with his lone win coming in a squash match against Gilles Arsene (who?... exactly).
Wanderlei on the other hand had knocked out four of his five opponents since last meeting Sakuraba, the only fighter managing to survive being heavyweight kickboxer Mirko Cro Cop in a special rules bout (as there were no judges for the special bout, it was declared a draw after fifteen minutes of action though Wanderlei had clearly won the fight).
When the two were paired up for the third time in the opening round of PRIDE's 2003 Middleweight Grand Prix, there was little doubt as to who would emerge the victor; Sakuraba was clearly on the decline while Wanderlei had emerged as one of the most feared knockout artists on the planet.
Though he valiantly tried to strike with Silva after failing to take the champion down, Sakuraba would get viciously knocked out midway through the opening round by a vicious combination as he threw a leg kick.
It was an entirely expected yet no less depressing loss, a legend in the sport getting knocked out in brutal fashion in a fight he had no place being in. There's a reason it made the list of trilogy fights that never should have happened.
Aging vets being fed to young lions are certainly a recurring theme in MMA and they're often depressing bouts for longtime fans of the sport, but when it happens with a fighter that's already lost twice to the same hungry young lion, it just becomes disturbing.
11. Antonio Rodrigo Nogueira getting his arm snapped by Frank Mir
By the time Antonio Rodrigo Nogueira made his UFC debut in 2007, he was already a decorated legend in the sport of MMA.
The inaugural PRIDE heavyweight champion had been tapping out his opposition since 1999 and had beaten a who's who of the heavyweight division, from Mirko Cro Cop to Josh Barnett to Fabricio Werdum, the only unavenged losses in his career coming against the man many considered the greatest heavyweight in MMA history, Fedor Emilianenko.
Nogueira would add to his trophy case by submitting Tim Sylvia and capturing an interim UFC heavyweight title early in 2008 before running into fellow submission specialist Frank Mir at UFC 92; rather than engaging in a grappling match against a fellow BJJ black belt as fans had expected, Mir instead chose to keep the fight standing and showcase his improved boxing, picking Nogueira apart on the feet and dropping him three times en route to a second round TKO victory.
Mir became the first man to ever finish the legendarily durable Brazilian that night, and as time went on it became clear that the wars Nogueira had put his body through over the years were starting to catch up to him.
After a win over fellow vet Randy Couture, Nogueira was knocked out for a second time in just over two minutes against future champion Cain Velasquez. He then faced Brendan Schaub, who rocked the Brazilian early before Nogueira turned on the afterburners and felled the glass-jawed former NFL player to get back in the win column.
Mir would see mixed success himself following his victory over Nogueira; immediately following his capture of the interim title, Mir was viciously mauled by his rival Brock Lesnar in an epic grudge match at UFC 100, which inspired Mir to bulk up and add some muscle to his frame in order to compete with the new breed of massive heavyweights.
A much thicker Mir ran through Cheick Kongo before getting smashed in an interim title fight by the brick-fisted Shane Carwin. He then proceeded to engage in a near 15-minute snooze-fest against Mirko Cro Cop then knocked him out in stunning fashion in the last minute of the bout, the impressive finish completely overshadowed by the horrendously dull fight that had occurred up until that point.
A workmanlike decision win over Roy Nelson kept Mir on track but considering the once-exciting heavyweight had now been involved in two dull fights in a row and had lost two of three before that, he was in need of an impressive performance to get himself back into title discussions.
A rematch with Nogueira made sense for all involved, and so the second meeting between the two was set for UFC 140 at the end of 2011.
With a renewed focus on his boxing, Nogueira made the now-lumbering Mir look silly for packing on all that muscle as the aging Brazilian that Mir himself had made look ancient just a few years ago was now regularly beat him to the punch. Later in the opening round, Nogueira popped Mir with a stiff combination that wobbled him and had Frank desperately grabbing onto a leg to attempt a takedown.
Sprawling on Mir, Nogueira peppered his wounded prey with several left hands and had he continued to look for a TKO, given Mir's famously poor instincts on defending himself from strikes when hurt, in all likelihood Big Nog would have walked away the victor. Instead, Antonio looked to become the first man to ever submit Frank Mir as he locked up a guillotine choke and attempted to flip over into mount.
Despite being severely rocked, Mir's survival instincts in the grappling realm proved second-to-none as he rolled out of the submission attempt and wound up on top. Attempting to escape and take Mir's back, Nogueira soon found himself in all sorts of trouble as the American BJJ expert isolated his right arm and brilliantly transitioned into side control to look for a kimura.
As Mir began to crank on Nogueira's arm, the wily vet rolled in an attempt to free himself from the lock, but Mir rolled with him and once again ended up on top before he reefed on his victim's poor arm. Moments later Nogueira's upper arm snapped in half as the result of the most brutal submission in UFC history, forcing Nogueira to tap - but it was clearly too late.
The entire sequence was truly remarkable and it is one of the most sudden and dramatic comebacks you'll ever see in a fight - the fact that Mir could pull off a submission on one of the most decorated Brazilian jiu-jitsu black belts in MMA history moments after being rocked and nearly finished himself is simply absurd.
The submission earned Mir the accolades of being the first man to ever submit Antonio Rodrigo Nogueira (in addition to already being the first man to knock him out) and of being the first and only fighter in the UFC to break the limbs of his opponents with submission holds on two separate occasions (he also famously broke Tim Sylvia's arm years prior to capture the UFC heavyweight title).
As impressive as Mir's win was, it was equally devastating for Nogueira - the nasty fracture of his humerus required a plate with 16 screws to be inserted into his arm to mend the injury.
It was tough to see a legend of the sport be injured in such a gruesome manner and it was made all the more sad for Nogueira fans in knowing that he was so close to achieving victory - had he simply continued hammering away at Mir instead of opting to try and submit him, in all likelihood Nogueira would have picked up an impressive TKO victory instead of having his arm snapped in half like a popsicle stick.
If MMA isn't the most unforgiving sport in the world, I don't know what is.
10. Mirko Cro Cop getting Cro Copped
When Mirko "Cro Cop" Filipovic came over to the UFC in 2007, it was a big deal.
The Croatian kickboxer had made a name for himself as one of the most feared and devastating strikers in mixed martial arts over in PRIDE, racking up an impressive 21-4-2 record which included brutal knockouts over the likes of Igor Vovchanchyn, Mark Coleman, and Wanderlei Silva.
After tearing through the field and winning the PRIDE 2006 Openweight Grand Prix with four first round knockouts, a massive rematch with heavyweight champion Fedor Emilianenko failed to materialize after PRIDE and/or Fedor's management continued to avoid the matchup, and soon Cro Cop would sign a lucrative contract with the UFC instead.
Rather than getting an immediate title shot, the UFC opted to try to build Mirko's popularity in the US before putting him into a championship fight. As a result he made quick work of the undefeated Eddie Sanchez in his UFC debut before squaring off with BJJ black belt Gabriel Gonzaga in a heavyweight title eliminator.
Considered to be primarily a grappler, the burly Gonzaga did sport plenty of knockout power himself as evidenced by his brutal ground and pound and even an impressive superman punch knockout victory in his UFC debut.