ARCHIVAL (GOOD MORNING AMERICA, ABC NEWS, ):NEWS REPORT: Every autumn Sunday, footballs bone-shattering hits unhinge NFL players across the country.

NARRATION: Over the past several years, the National Football League has been shaken by the controversy over the long term impact of concussions.

ARCHIVAL (NBC NEWS, 5-17-15):LESTER HOLT: In a surprise announcement, star 49ers linebacker Chris Borland says hes retiring from the NFL after just one season.

CHRIS BORLAND (FORMER LINEBACKER, SAN FRANCISCO 49ERS): Around training camp there was an incident, just a mild concussion and it kind of changed the way I viewed the risks of the game. The mounting evidence and these anecdotes of guys who went through hell. By the end of the year, I had a good idea of what I was going to do. For 99.9 percent of the people in America, footballs just entertainment.

ARCHIVAL (MONDAY NIGHT FOOTBALL OPEN):ANNOUNCER: Well, its Monday night and were ready to strike!

CHRIS BORLAND: But the guys on the field are real. Theyre humans, and so I think its important to remember that.

NARRATION: Since Borlands abrupt retirement in 2015, other players have followed suit.

But this isnt the first time that the inherent violence of a sport has raised questions about its future. Thirty-five years ago, it was boxing.

RICK GENTILE (FORMER CBS SPORTS EXECUTIVE): In the old days, you might turn on the TV on a weekend afternoon and three networks would have a boxing match on. In 82, particularly, there was an NFL strike and, figuring NFL fans are going to want to see action sports, we replaced it with boxing.

ARCHIVAL (CBS):TIM RYAN: Mancini is enjoying being a world champion.

NARRATION: In 1982, Ray Boom Boom Mancini, the pride of Youngstown, Ohio, had won his first world lightweight championship.

ARCHIVAL (CBS SPORTS, 11-13-82):RAY MANCINI: I worked so hard to get it Im not about to give it up now.

RICK GENTILE: Ray Mancini was a very, very popular champion. His whole persona was of being just this nice kid from Ohio. The ratings for Mancini fights were great, our highest ratings of any fighter we were doing.

NARRATION: In November of that year, in a Las Vegas stadium before a live CBS audience, Mancini was set to defend his title against a little-known Korean challenger.

ARCHIVAL (CBS SPORTS, 11-13-82):RING ANNOUNCER: Fighting out of Seoul, Korea, weighing 134 and 1/4 pounds. Here is Duk-Koo Kim.

RICK GENTILE: We had never heard of Duk-Koo Kim before that, but we would look at film, videotape, whatever we could get of him fighting and we knew he was a very tough guy. We didnt want a guy who was going to run. We wanted somebody who would stand there and exchange. And that was Kims style.

ARCHIVAL (CBS SPORTS, (11-13-82):TIM RYAN: And theres the bell and we are underway

RAY MANCINI (FORMER WBA LIGHTWEIGHT CHAMPION): Kim built a coffin and he put it next to his bed, and he told his people, Either Mancinis going home in that or Im coming home in that. He put on his lampshade, Kill or be killed. To him it was a live or die situation.

RICK GENTILE: It was a brutal fight. In fact, Kim was the aggressor more than Ray, for most of the fight. But there was never a point where you thought one guy was beating the other guy to the point where a referee should have stepped in.

ARCHIVAL (CBS SPORTS, 11-13-82):TIM RYAN: Duk-Koo Kim. You may not have heard of him before, you will remember him after today. Win or lose.

RAY MANCINI: I was hitting him with shots, but he was still moving and making me miss, too. He still had the wherewithal to move his body, slip, bob and weave. You cant stop a fight when a guy has the wherewithal to do that.

It was a great punch. I hit him with the right shot and he went down. We just jumped. It was glorious because it was a great win. Nobody knew thewhat was going into it. Nobody knew.

ARCHIVAL (CBS SPORTS, 11-13-82):RAY MANCINI: I planned on a long fight. Everybody didnt know about that. I saw films, the guy was very impressive. Tough, rough, hungry, determined, those are the worst kind.

RICK GENTILE: The next morning I called and said, Whats going on? And he was still in the hospital in bad shape. And then it was pretty muchwe all knew what was going to happen. You know, he wasnt coming out of this.

RAY MANCINI: I was stunned, I was like in a dream world, you know, from the highest of highs to the lowest of lows.

ARCHIVAL (ABC, 11-14-82):DIANE SAWYER: A professional boxer lies near death tonight. He is Duk-Koo Kim, a 23-year-old South Korean lightweight.

ARCHIVAL (CBS NEWS, 11-17-82):DAN RATHER: The boxers mother pleading with him to please wake up and open eyes before she was led from the room, weeping.

RAY MANCINI: When you fight fighters from another country, theyre fighting for more than themselves. Theyre fighting for their whole country. Theyre carrying the dreams and hopes of their countrymen on their backs. Thats a load to fight. Thats a hard load to fight.

NARRATION: Kims death was far from boxings first black eye. In the early 60s, fighters Benny Paret and Davey Moore died in back-to-back years after major fights broadcast across the country.

KIERAN MULVANEY (BOXING ANALYST): At that point there was a sense of, Well, is boxing even really a sport? Then in the mid-70s you have the sense of impropriety that has been an aspect of boxings DNA for many decades. And then in 82 you had Ray Mancini and Duk-Koo Kim.

GEORGE LUNDBERG (FORMER EDITOR, JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION): And then, two weeks later Im watching and theres this fight with Randall Tex Cobb and Larry Holmes.

ARCHIVAL (ABC, 11-26-82):HOWARD COSELL: Just terrible. I wonder if that referee understands that he is constructing an advertisement for the abolition of the very sport that hes a part of?

GEORGE LUNDBERG: Cobb was a punching bag. I mean, his head was just bobbing back and forth, on, and on, and on.

ARCHIVAL (ABC, 11-26-82):HOWARD COSELL: From the point of view of boxing, which is under fire and deservedly so, this fight could not have come at a worse time.

GEORGE LUNDBERG: And I just said to myself, This is crazy. How can I, as a physician, possibly admire this, enhance it, support it, and not work against it?

ARCHIVAL (CBS, 1-14-83):DAN RATHER: Boxing attracts big television audiences. It has drawn the attention of writers from Virgil to Hemingway to Norman Mailer. But today the American Medical Association came out swinging against the sport.

ARCHIVAL, (ABC 1-14-83):NEWS REPORT: The AMA Journal says that boxing is an obscenity that should not be sanctioned by any civilized society.

ARCHIVAL (ABC 1-14-83):DR. GEORGE LUNDBERG (AMA JOURNAL EDITOR): The purpose of the boxing match is for one person to injure his or her opponent. Now when one knocks somebody out, one damages the brain, one tears brain cells.

RICK GENTILE: I dont think fight fans said, Okay, thats it. Im never going to watch another fight, just as they didnt say, Okay, Im never going to smoke another cigarette, when they put a warning on the pack. But sponsors started to pull back and say, You know, youre asking us for a lot of money, you networks, to pay for your exorbitant rights fees on football and basketball and baseball. And with all the bad publicity boxing is getting, you know what, we just as soon not do it.

RAY MANCINI: Before the Kim fight, I was being offered all kind of endorsement deals. After that, everything went away, man. It just vanished. I understand that now. I understand now. But at the time I was like, I was a kid. I was heartbroken. I didnt know why. You know? It just, it all went away.

NARRATION: For decades, stories of young boxers from blue-collar backgrounds fighting their way to fortune had captivated the public both in real life.

ARCHIVAL (NBC, 5-11-84):CHILD BOXER: I do it because Ill leave, Ill leave the ghetto.

NARRATION: and on the big screen.

ARCHIVAL (CLIP FROM THE MOVIE ROCKY)

NARRATION: But before long, the medical community began to make inroads in their fight against the sport.

GEORGE LUNDBERG: The American Academy of Pediatrics came out with a formal position that children shouldnt box. I took a position that, for any parent who put their child into a boxing situation, that should be considered child abuse.

NARRATION: And on television, beer companies were soon the only marquee advertisers still associated with boxing.

ARCHIVAL (BUDWEISER AD, 1979):The WBC heavyweight championship fight is being brought to you by Budweiser. For all you do, this Buds for you.

KIERAN MULVANEY: Sponsors withdraw, so network TV doesnt want to broadcast it. So people dont see as much boxing, so they dont know as much about it, so sporting media doesnt write about it as much because they say people dont watch boxing, theyre not interested in it. And because media isnt reporting on, people learn about it even less. It becomes this feedback thing and before you know it, suddenly its a niche sport.

ARCHIVAL (CNN, 10-7-96):ANNOUNCER: The legendary Julio Cesar Chavez returns to the ring, Saturday, October 12, on Pay-Per-View!

KIERAN MULVANEY: Theres something fundamental and primal about boxing. But as society shifts, there are legitimate questions of, Well, do we still want to do this? Its that drip, drip, drip, that constant sense that that is what boxing is about. If that becomes the prevailing feeling about football, then the discussion changes.

JONATHAN MAHLER (STAFF WRITER, THE NEW YORK TIMES MAGAZINE): Look, at this point, we know how dangerous football is. Anyone who continues to believe that professional football players arent potentially shortening their lifespan by playing this game is of living on another planet.

ARCHIVAL (ABC 5-4-12):NEWS REPORT: Meantime, more players are suing the NFl, claiming the league failed to properly protect them from concussions and brain injuries during their careers.

NARRATION: Faced with medical evidence about the health risks posed by the game, the NFL has started making payments to retired players who have suffered brain trauma payments that could total as much as one billion dollars.

ARCHIVAL (NFL AD):If there is a way to do it better.

NARRATION: The league has also promoted its efforts at making the game safer.

ARCHIVAL (NFL AD):Changes were made to the kickoff this year, important changes.

NARRATION: All aimed at addressing the criticism of a sport with more money and power than any in American history.

ARCHIVAL (FOX NEWS SUNDAY, 2-2-14):CHRIS WALLACE: You now make about $10 billion a year in gross revenue. You said that by 2027 you would like to see $25 billion.ROGER GOODELL: We dont want to become complacent.

RICK GENTILE: The NFL has a big issue in the concussion, the head injury situation, huge issue. But, there is an entity called the National Football League. Theres a controlling entity, a managing entity. Football has the NFL to solve its problems or at least attempt to solve its problems. It has a PR machine to tell the public that were working on this. Boxing was controlled by promoters and the networks back in the day. So there was no such thing as boxing. It had no ability to defend itself because theres no organization. And that might have been one of the biggest problems they had.

NARRATION: The future of football is playing out on local fields around the country, where flag football is gaining popularity after news stories about concussions in high school players.

JONATHAN MAHLER: There is certainly a double standard. If you support football in the sense that you watch it, and then turn around and dont allow your child to play it. The question is kind of like by watching it are you necessarily condoning it? Its so ingrained in our culture that it does take a kind of real act of like protest and resistance to-to turn away from it.

NARRATION: Over three decades have passed since the Kim/Mancini fight stoked medical concerns about boxing.

Then in one week in July 2019..

ARCHIVAL (JULY 2019): TRAINER: Max, Im going to stop it, Max. Youre getting hit too much.

NARRATION:…Two boxers died from injuries suffered in the ring. But compared to the swiftness with which boxing was relegated to the sidelines of American life, football still holds its appeal.

KIERAN MULVANEY: If somebody were to die during an NFL game being broadcast live, the massive social media response, would that cause a greater, perhaps long-term response? Or would it mean that everyone went through the cycle of grief and outrage in a couple of days until Kim Kardashian did something else? I dont know. Im very curious to see what happens in society over the next decade or two.

(END)