Yes, that actually happened. UFC star Conor McGrgeor and boxing legend Floyd Mayweather went toe-to-toe in the ring on August 26 at the T-Mobile Arena in Las Vegas -- and it was a crowd-pleaser. Despite early action from McGregor, Mayweather dominated the late rounds and knocked his Irish opponent out midway through the 10th round.
"Tonight is my last fight," Mayweather said in the ring afterward. "For sure."
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Floyd Mayweather defeats Conor McGregor by TKO in 10th round
Floyd Mayweather defeated a game but tiring Conor McGregor by TKO in the 10th round Saturday night at the T-Mobile Arena in Las Vegas. Referee Robert Byrd stopped the bout at 1:05 of the 10th round. -- Dan Rafael
Mayweather's win goes as planned
Andre Ward says Floyd Mayweather followed a methodical fight plan to score a 10th-round TKO win over Conor McGregor, although he was surprised how much Mayweather was hit.
One-Play: Mayweather wins by TKO in 10th round
After a dominant ninth round, Floyd Mayweather puts away Conor McGregor in the tenth.
Ringside Seat: The complete guide to Mayweather-McGregor
All eyes will be on Las Vegas Saturday night as Floyd Mayweather faces Conor McGregor. Here's everything you need to know about the mega-fight between the stars of the combat sports world. -- Dan Rafael
Mayweather issues '100 percent' KO guarantee
Floyd Mayweather, saying he wants to re-enter retirement with a memorable finale, says he will knock out Conor McGregor. "One hundred percent, it will not go the distance," he said. -- Dan Rafael
$1M bets on Mayweather spark odds shakeup
After the MGM sportsbook took a $1 million bet on Floyd Mayweather, William Hill reported a $1.2 million wager on the undefeated boxing champ, whose odds to beat Conor McGregor were back at minus-600 at multiple spots in Las Vegas. -- David Purdum
Mayweather or McGregor? Athletes make their picks
Will Conor McGregor or Floyd Mayweather prevail in Saturday night's boxing match? Dez Bryant, Rory McIlory, Mike Trout and other athletes give us their predictions for the fight. -- Ben Fawkes
Floyd Mayweather bets big, just not on himself
Floyd Mayweather is known as a big bettor in Las Vegas, consistently making six- and seven-figure wagers on sports. But will he bet on himself against Conor McGregor? Those who know his betting habits say he won't -- and never has -- bet on himself. -- David Purdum
That time when Mayweather got rocked
Floyd Mayweather is a master boxer and perhaps the greatest defensive fighter of all time, so the question is: Can Conor McGregor hurt him? Shane Mosley did in 2010. -- Dan Rafael
What's the weirdest way Mayweather-McGregor could end?
What's the worst that could happen? Boxing has a long history with bizarre endings. -- Oliver Roeder and Brin-Jonathan Butler
Why Floyd Mayweather can still box after beating women
No photos, no central authority and black victims. -- Soraya Nadia McDonald and Lonnae O'Neal
Conor McGregor happy with smaller gloves, but sees pros and cons to it
UFC star Conor McGregor had agreed to box Floyd Mayweather Jr. in 10-ounce gloves, per Nevada State Athletic Commission rules, but was pleased that the panel agreed at its monthly meeting Wednesday to allow them to wear 8-ounce gloves. -- Dan Rafael
Why Mayweather-McGregor is alarming Vegas oddmakers
Mayweather-McGregor will be the most-bet boxing match in Nevada's history when the fight happens on Saturday, Aug. 26. But even Las Vegas oddsmakers with decades of experience have been surprised at the betting patterns -- and where the line may still go. -- Doug Kezirian
Top stats to know: Mayweather vs. McGregor
While we all thought Mayweather-McGregor would just be a myth, the reality is it will happen this Saturday. ESPN Stats & Information gives you the top stats to know heading into the fight. -- ESPN Stats and Information
Mayweather Promotions CEO says fight has done $60M at box office
Mayweather Promotions CEO Leonard Ellerbe said Thursday that the Floyd Mayweather-Conor McGregor fight was on pace to break the boxing gate record despite characterizations suggesting otherwise. -- Darren Rovell
How the WWE would book Floyd Mayweather vs. Conor McGregor
The circus surrounding the Floyd Mayweather-Conor McGregor fight has some pure fight fans shaking their heads at the spectacle, but what if they turned up the melodrama to 11 by crossing over into the WWE Universe? We imagine how it would all play out. -- Andrew Goldstein
Tale of the Tape: Why Conor McGregor vs. Floyd Mayweather is a lopsided match
It's the best boxer of his generation, Floyd Mayweather Jr. (49-0, 26 KOs), against a mixed-martial artist with no professional boxing record whatsoever, Conor McGregor. Who will emerge on top in the spectacle of the year? ESPN's boxing and MMA experts, Dan Rafael and Brett Okamoto, agree: it's going to be a looooooong night for the brawler from Dublin. -- Brett Okamoto/Dan Rafael
Female fighters weigh-in: What challenges await Mayweather and McGregor?
Claressa Shields, Michelle Waterson, Heather Hardy and Joanna Jedrzejczyk are at the top of their fighting game. What do these boxers and MMA fighters think awaits Conor McGregor and Floyd Mayweather in their upcoming bout? -- Sunni Khalid
Before Mayweather-McGregor, there was Ali-Inoki
For another moment quite like this, perhaps, even, the moment that made this moment happen, one has to go back 41 years ago and about 5,500 miles west of Las Vegas. On June 26, 1976, the world's heavyweight champion Muhammad Ali took on Japanese wrestler Antonio Inoki in another glorified exhibition billed as "The Martial Arts Championship of the World." -- Sunni Khalid
Mayweather-McGregor card adds title bouts
World titleholders Gervonta Davis and Nathan Cleverly will defend their belts on the undercard of the Floyd Mayweather-Conor McGregor fight on Aug. 26 at the T-Mobile Arena in Las Vegas, Mayweather Promotions announced Thursday. -- Dan Rafael
Conor McGregor is defined by and rebels from his Dublin roots
Dublin is best understood by exploring its many divisions, its unending physical and mental boundaries. The city is defined by those limits, as is McGregor. -- Wright Thompson
Why Mayweather's sparring partners don't give McGregor a chance
Errol Spence Jr., Zab Judah and other professional fighters who face Mayweather daily marvel at what makes him unbeatable. -- Dotun Akintoye
McGregor striking coach Owen Roddy discusses camp, advantages over Mayweather
Conor McGregor is a heavy underdog in his Aug. 26 boxing match with legend Floyd Mayweather. And that's just how Owen Roddy, McGregor's longtime striking coach, likes it. In an exclusive interview with ESPN, Roddy details McGregor's progress in the sport. -- Brett Okamoto
All the ways you can bet Mayweather-McGregor
Think Conor McGregor can beat Floyd Mayweather by knocking him out? What about within the first 60 seconds of the fight? Those are only two of the wide variety of bets available at sportsbooks for the Aug. 26 showdown in Las Vegas. -- Ben Fawkes
'The Super Bowl of boxing': How Vegas made Mayweather-McGregor odds
Nearly four months before the Floyd Mayweather-Conor McGregor fight was official, Las Vegas bookmakers put out a line. Here is how they came up with odds on the bout (so far most of the money is being bet on McGregor). -- David Purdum
Biggest bets for Mayweather-McGregor
One bettor has already wagered $150,000 (at William Hill US) on Conor McGregor to beat Floyd Mayweather. Here is a running file of the biggest Mayweather-McGregor bets across Nevada sportsbooks. -- David Purdum
White reflects on Mayweather, McGregor mind games, addresses controversial comments
UFC President Dana White spent the last week in Los Angeles, London, New York and Toronto promoting the Floyd Mayweather vs. Conor McGregor boxing match. In an exclusive interview with ESPN, White looks back at the tour and addresses the controversy surrounding it. -- Brett Okamoto
Alvarez: 'Very real chance' McGregor knocks out Mayweather
Eddie Alvarez knows better than most what it takes to face Conor McGregor, as they fought at UFC 205 in New York last year. Alvarez provides a unique look at what Floyd Mayweather is preparing for in the McGregor-Mayweather boxing match in August.
Has McGregor psyched out Mayweather?
ESPN's Steve Bunce shares his thoughts on Floyd Mayweather's and Conor McGregor's recent world press tour.
Mayweather-McGregor tour sold hate, not a fight
The Floyd Mayweather-Conor McGregor promotional tour sunk to new depths of racism, homophobia and misogyny. -- Mike Wise
How top MMA trainers would prepare McGregor for Mayweather
How should MMA star Conor McGregor -- with no professional boxing fights on his resume -- approach his bout with Floyd Mayweather? Brett Okamoto asked many top trainers for their strategy. -- Brett Okamoto
Who is Mayweather?
An elite group of fighters are reflections of the ethos in which they boxed. Floyd Mayweather is undoubtedly the best fighter of his generation, and he got there based on pure talent and a larger-than-life personality. -- Nigel Collins
Scoring the Mayweather vs. McGregor news conferences
The four days of news conferences were the fights before the fight. How would judges score the verbal battle between Floyd Mayweather and Conor McGregor? We have a winner. -- Dan Rafael and Brett Okamoto
Mayweather-McGregor world tour was a spectacle ... and thankfully it's over
The Floyd Mayweather-Conor McGregor world tour was indeed entertaining but also extremely disturbing given some of the actions and words of the fighters. -- Arash Markazi
Are we going to go on validating the Mayweather-McGregor trash talk?
We all knew the buildup to the Floyd Mayweather-Conor McGregor fight would feature posturing and hyper-masculine aggression. But it's quickly devolved into bigotry and misogyny, and espnW's Sarah Spain asks: Are these people deserving of our admiration? -- Sarah Spain
McGregor: I beat Floyd in trash-talk battle
Conor McGregor insisted that he won the four-round trash-talking battle with Floyd Mayweather Jr. after enjoying a raucous 29th birthday party at the London media event on Friday. -- Nick Parkinson
Mayweather: 'My legacy is already set'
Floyd Mayweather had no desire to return to the ring -- until the opportunity to fight Conor McGregor arose. Now Mayweather says he has no interest in coming back after the Aug. 26 megafight. -- Dan Rafael
The best of Mayweather-McGregor world tour
Four cities and three countries over four days: Floyd Mayweather and Conor McGregor traded verbal jabs from one city to the next.
McGregor hasn't gotten under Mayweather's skin
Floyd Mayweather says Conor McGregor's antics haven't affected him and adds that he respects that McGregor believes in himself.
Mayweather: I'm the biggest name in MMA and boxing
Floyd Mayweather talks to Sal Paolantonio about throwing money at Conor McGregor, making reference to a Las Vegas gentleman's club, and why the news conferences have created such a large draw.
McGregor's coach fires warning to Mayweather
Conor McGregor's UFC coach, John Kavanagh, has warned Floyd Mayweather that the Irishman's boxing skills are improving all the time. -- ESPN.com news services
Mayweather, McGregor fuel drama in 2nd news conference
Floyd Mayweather and Conor McGregor hype their megafight and relentlessly needle each other in the second news conference of their world tour.
Floyd gets Irish flag, Conor grabs Floyd's backpack
Floyd Mayweather tricks a fan into throwing him an Irish flag. Instead of giving it to Conor McGregor, Mayweather drapes it over his shoulders. McGregor responds by doing a search of Mayweather's money-filled backpack.
IRS: Mayweather owes $22.2M on 2015 taxes
Floyd Mayweather Jr. still owes $22.2 million in taxes from 2015, according to the IRS. -- ESPN.com news services
Mayweather, McGregor keep the hype growing
Check out the best quotes and photos from Floyd Mayweather's and Conor McGregor's first press conference ahead of their Aug. 26 bout.
Floyd-Conor tour begins with insults, taunts
Floyd Mayweather and Conor McGregor treated nearly 11,000 fans to a "great spectacle" of verbal jabs on Tuesday, when the two brash fighters faced off for the first time to launch a joint promotional tour for their Aug. 26 boxing match. -- Brett Okamoto
Mayweather, McGregor trade barbs on stage
Floyd Mayweather busts out a $100M check while Conor McGregor mocks Mayweather's tax problems.
McGregor makes bold -- and profane -- fashion statement
UFC lightweight champion Conor McGregor showed up at the first stop of a press tour to promote his fight with Floyd Mayweather Jr. wearing a custom three-piece suit with a hidden message in the pinstripes. -- Adam Reisinger
Vote! Price for Mayweather-McGregor fight is set; would you pay for it?
The fight will cost $89.95 on pay-per-view, the same as the most expensive Mayweather-Pacquiao fight, with a $10 fee for HD. Will you pay for it? -- ESPN.com news services
Hype men: Mayweather, McGregor to start tour
Floyd Mayweather Jr. and Conor McGregor will visit Los Angeles, Toronto, New York and London next week to promote their megafight on Aug. 26. -- ESPN.com news services
The incredibly long odds of McGregor against Mayweather
Soon after the fight with Floyd Mayweather was confirmed, tons of small bets came in on Conor McGregor. It's a good thing they were small. Many can't fathom the extent of this mismatch. -- Bill Barnwell
Price to sponsor Mayweather-McGregor: $10M
The asking price to be the title sponsor of the Floyd Mayweather-Conor McGregor fight is $10 million. -- Darren Rovell
Mayweather-McGregor: Expect a spectacle, not a fight
If you are interested in the Floyd Mayweather-Conor McGregor fight, cool. Enjoy. Have a party. Have a blast. But manage your enthusiasm and don't expect a good bout. -- Dan Rafael
The reality missing in the Mayweather-McGregor hype
The Floyd Mayweather-Conor McGregor fight is a soulless money grab featuring one of the most flawed superstars in all of sports. -- Sarah Spain
White won't defend McGregor-Mayweather fight
Dana White tells Max Kellerman that people expect him to defend the impending bout, but says, "I didn't make this fight, the fans made this fight."
McGregor-Mayweather fight a 'sucker's paradise'?
Stephen A. Smith doesn't think fans interested in the McGregor-Mayweather bout are necessarily "suckers," as Dan Le Batard says.
Mayweather-McGregor: What does it mean for the sports of boxing and MMA?
The fight between Floyd Mayweather and Conor McGregor is set, but what will their decision to fight have on the growth potential of their respective sports? -- Dan Rafael and Brett Okamoto
How Floyd Mayweather vs. Conor McGregor came to be
A timeline of the verbal sparring that led to the most unlikely fight of the year: Floyd Mayweather vs. Conor McGregor.
Megafight principals all agree: Closing Mayweather-McGregor deal came off smoothly
The now-official Floyd Mayweather-Conor McGregor megafight was not that difficult to pull off once the talks turned serious, the three principals of the Aug. 26 blockbuster fight told the media on a conference call.
It's on: Mayweather-McGregor fight finalized
The much-anticipated boxing match between undefeated Floyd Mayweather Jr. and MMA superstar Conor McGregor will take place Aug. 26 in Las Vegas. -- Dan Rafael
The science behind Mayweather-McGregor
ESPN Sport Science breaks down the power UFC champion Conor McGregor will bring to the boxing ring against the defensive prowess of Floyd Mayweather.
McGregor does work at news conferences
A news conference with Floyd Mayweather and Conor McGregor is sure to include fireworks. Look back at a few of McGregor's best moments on the dais.
Rovell thinks Mayweather-McGregor could set PPV record
Darren Rovell estimates the Mayweather-McGregor bout could surpass the pay-per-view record set by Mayweather-Pacquiao two years ago, but thinks ticket sales could be less.
Sonnen says let's enjoy megafight
MMA fighter Chael Sonnen acknowledges that Conor McGregor will be a huge underdog against Floyd Mayweather but adds that the event will be fun.
McGregor's fast road to enormous payday
Brett Okamoto describes the amazing journey Conor McGregor has been on since starting on a UFC undercard in 2013, all the way to a superfight with Floyd Mayweather on Aug. 26.
How much money will Mayweather-McGregor make?
Will Floyd Mayweather's fight against Conor McGregor make more money than his bout with Manny Pacquiao in 2015? Darren Rovell breaks down all angles of the projected finances. -- Darren Rovell
De La Hoya takes 'high road' on White criticism
Promoter and legendary former boxer Oscar De La Hoya took the high road in response to recent criticism from UFC President Dana White, and said a potential bout between Floyd Mayweather and Conor McGregor "is going to suck." -- ESPN.com news services
UFC's White blasts 'two-faced' De La Hoya
UFC President Dana White ripped boxing promoter Oscar De La Hoya for badmouthing the proposed superfight between Floyd Mayweather Jr. and Conor McGregor. -- Brett Okamoto
De La Hoya warns fans off Floyd-Conor 'circus'
Oscar De La Hoya, one of boxing's most significant promoters, issued an open letter to boxing fans on Thursday slamming the proposed match between Floyd Mayweather and Conor McGregor. -- Dan Rafael
Hatton: McGregor won't lay a glove on Floyd
Boxer Ricky Hatton believes Conor McGregor and the UFC face embarrassment if McGregor fails to "lay a glove" on Floyd Mayweather -- just as Hatton, Oscar De La Hoya and Canelo Alvarez failed to -- if the proposed superfight goes ahead. -- ESPN.com news services
Coach Kavanagh: McGregor already training for Mayweather
Conor McGregor's coach, John Kavanagh, spoke exclusively with ESPN about how McGregor is preparing for his boxing match against Floyd Mayweather. -- Brett Okamoto
McGregor applies for boxing license in Nevada
Conor McGregor has applied in the state of Nevada for a pro boxing license ahead of a potential blockbuster fight with Floyd Mayweather. -- Brett Okamoto
McGregor terms set; talks shift to Mayweather
UFC lightweight champ Conor McGregor says he has agreed to a "record-breaking deal" to fight Floyd Mayweather. UFC President Dana White says Floyd Mayweather must still sign off on the bout. -- ESPN.com news services
Is McGregor fast enough to dodge Floyd?
Analyst Max Kellerman debunks the idea that Conor McGregor is immune to getting knocked out by Floyd Mayweather.
Stephen A. expects McGregor to be 'schooled' by Mayweather
ESPN's Stephen A. Smith addresses the odds for a potential Floyd Mayweather-Conor McGregor bout, and acknowledges McGregor's ability to drop opponents with a single punch.
De La Hoya says Mayweather-McGregor fight 'bad for both sports'
Oscar De La Hoya explains why he thinks the proposed megafight between Floyd Mayweather and Conor McGregor would be bad for both MMA and boxing.
Watch: Mayweather and McGregor in their own words
Floyd Mayweather and Conor McGregor are not only two of the best fighters in their respective sports but also two of the strongest talkers. Look back at some of their biggest verbal jabs over the years.
Rafael says McGregor 'has virtually no chance' against Mayweather
Dan Rafael says that the general consensus from the boxing and MMA communities is that Conor McGregor is mismatched against Floyd Mayweather in a boxing contest.
McGregor yells to Rafael, 'I am boxing!'
Dan Rafael describes his confrontation with Conor McGregor ringside at a boxing match in New York City. McGregor went face to face with Rafael, and the UFC star said he'll shock the world by defeating Floyd Mayweather.
Mayweather to McGregor: 'Sign the paper'
Floyd Mayweather says Conor McGregor should "sign the paper" as talk over a potential superfight bubbles again. -- Ben Dirs and Rob Bartlett
Mayweather takes digs at 'Conor McTapout'
Floyd Mayweather posted an Instagram video of Conor McGregor tapping out at UFC 196 and offered $10,000 for the best caption posted about the video. -- ESPN.com news services