Casualty in the Ring

""Sure there have been injuries and deaths in boxing, but none of them serious.""

- Alan Minter, former British boxing champ

Ten seconds, and our boxer is down for the count. He's knocked out, but he'll get back on his feet eventually... no, he won't. He's crippled for life, if he's not outright dead. You can stop applauding the victor now. Deaths like this might seldom happen in Real Life, but it's none the less Truth in Television.

Anime And Manga

 * At least two characters in the boxing manga Ashita no Joe die in the ring, or immediately after a fight.
 * Apparently the first death, of Tooru Riikishi, was so well-done that fans of the manga held a memorial service for the character. The main character Joe Yabuki also goes through a long Heroic BSOD because of this, since Riikishi was The Rival to him... and Joe is the cause of such death, as a too-well cross-counter from him causes Riikishi enough brain damage to drop dead right after the fight was over.
 * The second death was... of Joe himself, who Goes Out With A Smile after hearing the decision on his match with the World Champion. This death has become a Stock Shout Out.
 * In Katekyo Hitman Reborn, this trope is the reason why Knuckle, the Sun Guardian for the First Vongola Boss, swore off boxing and became a priest.
 * Subverted in Hajime no Ippo. While Randy Boy Sr. sustained fatal brain damage in his fight with Miyata's father, said damage didn't manifest itself until several days after Randy Sr's world championship fight. He didn't die in the ring per se, but the fight with Miyata Sr. caused his death nonetheless.
 * Also subverted with Jinpachi Nekota, who was a victim of a "rabbit punch" that caused him punch drunk disease (see below), but that happened sixty years ago and he's still alive. He did have to retire, though.
 * Used in the backstory of Karate Shoukoushi Kohinata Minoru. Ibuki Kengo's older brother Satoru, a martial arts genius, dies from intracranial hemorrhage due to the injuries he sustained in a match against an even greater Muay Thai fighter, Samart Sirinto. Ibuki Satoru had a cerebral arteriovenous malformation, a congenital disorder which placed him in great danger should he experience heavy head trauma, which had not been formally diagnosed before his death, but his fiancee believes that the medical examiners discovered it in his pre-fight medical examination and allowed him to fight anyway at the behest of the director of the fight promotion.

Film

 * In Million Dollar Baby, Maggie is hit from behind, lands on a corner stool and breaks her neck, leaving her a quadriplegic. Her mentor ultimately has to make the painful decision to end her life before leaving boxing for good.
 * The plot of Kickboxer is kicked off by the antagonist Tong Po beating Eric, the protagonist's brother, so badly that he's paralyzed from the waist down.
 * Apollo Creed in Rocky IV.
 * Happens offscreen in Pulp Fiction, with the protagonist as the winner. This gets him in serious trouble with Marsellus Wallace, because he was supposed to throw the fight for him.
 * A major plot point in The Quiet Man. John Wayne's character killed a man in the ring and swore off boxing forever. (Otherwise, the cross-country donnybrook would probably happened in the first reel, instead of the finale.)
 * Cinderella Man shows this happening to two of Max Baer's other opponents. (Someone points out that Primo Carnera's huge height advantage saved him - instead of dying, he only got mauled.)
 * In 1956's The Harder They Fall Humphrey Bogart's last film, Max Baer plays bloodthirsty boxer Buddy Brannen, a character based on himself. After another boxer dies in a match with Toro Moreno (whose character was based on Primo Carnera), Brannen in intent on proving that he, who badly injured the boxer in his previous match, is really responsible for the death.
 * The 2008 film The Wrestler has an implied example of this right at the end when the main character wrestles with a fatal heart condition, and takes one final plunge into the ring. Unusual in that his opponent isn't responsible for his death (even accidentally) and in fact tries to get him to stop once he realizes that he is not well.
 * The protagonist Superargo contro Diabolikus does this accidentally during a wrestling match.
 * Ong Bak has this as part of the back story for the main character's master, which is the reason he tells him never to use Muay Thai for anything other than self-defense.
 * Ip Man 2 has the Twister's fatal No-Holds-Barred Beatdown of Master Hung.

Literature

 * The book Flash Forward, upon which the TV series was very loosely based, invokes this. One character who didn't have a flash forward was told by someone who heard a report about his death that he had died in the ring, and he goes through the rest of his life wondering how that's going to happen, since he's not really into boxing.

Live Action TV

 * CSI had an episode where this happened. It turns out the dead guy
 * One episode of Leverage relied on faking one of these in order to snare a corrupt local fight promoter.
 * One season of Oz features a boxing tourny, climaxing with the death of one of the combatants.
 * Cold Case features an amateur boxer dying in the ring against a clearly superior opponent, with investigators wondering why the referee didn't stop the fight.

Music

 * Warren Zevon sings about the death of boxer Kim Duk Koo (see Real Life below) in his song "Boom-Boom Mancini."
 * Pettinellis' "Un hombre muerto en el ring" aka "Dead man on the ring".

Opera

 * Joe in The Rise and Fall of The City of Mahagonny.

Video Games

 * Fallout 2 has a boxing sidequest. The rules for winning a match are a little obscure, but death is definitely a possibility. Especially if you find the plated gloves and maybe pop a couple Buffout.
 * EA's Mutant League series of sports games revolved entirely around this, where players could be blown up on the court, bisected, etc.
 * This is a quintessential part of Mortal Kombat, though that shouldn't be surprising.

Web Original

 * Part of Bobby Jacks' backstory in Survival of the Fittest is that he accidentally killed an opponent in a boxing match.

Western Animation

 * In Justice League Unlimited, Green Arrow faked his death in a fight in order to shock his opponent out of competing in underground prize fights.

Real Life

 * On November 13, 1982, Duk-koo Kim lost to Ray Mancini by TKO in the 14th round at Caesar's Palace. Minutes later, Kim collapsed, went into a coma, and died five days later. This event led the three main boxing organizations of the 1980s to reduce the maximum length of title fights from 15 to 12 rounds and make pre-fight health checks more thorough.
 * As referenced in the entry for Cinderella Man above, Max Baer did, in fact, kill an opponent in the ring. However, contrary to his movie depiction, he felt really bad about it, and made amends to the man's family. Also, it only happened once.
 * Sadly, this happens more than just a few times in Real Life:
 * Benny Paret
 * Francisco Rodriguez
 * Benjamin Flores
 * Leavander Johnson
 * Johnny Owen
 * And at least one woman, Becky Zerlentes.
 * This happened to Professional Wrestling legend Mitsuharu Misawa after landing on his neck on an otherwise routine "backdrop" suplex, fatally injuring his spinal cord and suffering an in-ring heart attack.
 * This happened to British pro wrestler Malcolm "King Kong" Kirk after being on the receiving end of a signature splash from Big Daddy (easily the biggest name in British wrestling at the time), who was devastated by the incident despite an autopsy revealing that Kirk had a serious heart condition that cleared Big Daddy of any responsibility for his death.
 * In October 2001, Eiji Ezaki (FMW's headliner Hayabusa) botched a springboard moonsault against Mammoth Sasaki and broke his neck. He only recently regained the ability to walk. Without his presence, FMW folded. Ezaki is currently pursuing a career as a musician.
 * Due to the nature of many professional wrestling moves, one small slip-up can result in horrific injury. In addition to Eiji Ezaki, Darren Drozdov suffered a spinal-cord injury that left him a quadriplegic after a botched powerbomb. In addition, "Iron" Mike DiBiase suffered a fatal heart attack while wrestling; the incident was played into the origin story for his son, the "Million Dollar Man" Ted DiBiase.
 * JWP wrestler Plum Mariko died in 1997 after taking a Ligerbomb from Mayumi Ozaki. It was a routine spot, however Mariko's history of untreated concussions led to a brain abscess and taking the Ligerbomb caused her to fall unconscious and her brain to bleed. She died a few hours later.
 * The "Punch-Drunk Disease", which is the result of any sport where a player takes a serious blow to the head, keeps playing, and then takes a bunch more without the first getting a chance to heal (first identified in boxing, also found in wrestling and football) has led to quite a few deaths.
 * Bret Hart got seriously lucky in this regard. He suffered a concussion so severe that every blow he took to the head afterwards gave him a minor concussion. These days, he can't lift weights, fly in airplanes, or professionally wrestle. It was a miracle he didn't die outright. (This is why his in-ring work is so limited in his more recent WWE appearances.)
 * Luis Resto vs. Billy Collins is mired in controversy even after 30 years. Though Collins didn't die as a result of the match, the injuries he suffered in the ring, (which included permanent eye damage) ruined his entire livelihood. And about nine months later he died in a suspected suicide when it appeared that he deliberately crashed his car into a culvert. Then there are the other two reasons the bout is mired in controversy: Resto's trainer removed some of the padding from Resto's gloves, making the punches much more deadly, and according to Resto, gave the boxer crushed asthma pills mixed into his water, increasing his stamina. In other words Resto was able to hit much harder and for far longer than usual, leading to the severity of the injuries that Collins suffered.
 * In the case of Mixed Martial Arts, 30-year-old Michael Kirkham died from a brain hemorrhage after his pro debut, a TKO loss after being taken down and ground-and-pounded -- all legal strikes. but it would be later revealed that only a month before he'd been medically suspended (for thirty-days, this was after the suspension) after a TKO loss from strikes to the back of the head in his last amateur bout; on top of that, he was fighting in South Carolina where the sport had only recently become formally sanctioned but where neither a full physical nor a neurological test were required for a fighter's license, and most noticeably, he was fighting at lightweight (155 lbs) despite being six foot nine, making him dangerously lanky (and possibly having dehydrated to make 155).
 * It's actually been argued by many specialists that fighters drying out to make lower and lower weight classes may cause a fighter to be more prone to taking more sever damage. They point to the low number of ring deaths among heavyweights, who don't have to make weight before fights, even though they punch much harder than fighters in other weight classes. The above-mentioned Duk Koo Kim was reported to have had a monumental struggle to make weight for his title fight against Mancini, in a way understandable because this was a once in a lifetime chance (a title fight against one of America's most popular fighters at the time in Las Vegas on national television) for the obscure Korean boxer. These specialists believe the dehydration to try and make weight reduces the amount of fluid between the brain and the skull that cushions the brain during head trauma.