Recap: After a sluggish start, Floyd Mayweather finished off a surprisingly active Conor McGregor by a 10th-round TKO on Saturday night in Las Vegas. Mayweather announced that he would retire, ending his illustrious career with a 50-0 record before a non-sellout crowd of 14,623 at T-Mobile Arena.

For the first six rounds, it didn't look like the typical Mayweather who had dominated some of the best welterweights in the world with his masterful defense and counter-punching skills, as McGregor appeared to be more of the aggressor with from the opening bell. But by the ninth and 10th round, McGregor looked noticeably worn out and Mayweather took advantage of the fatigued Irishman, who was competing in his first professional fight. After a barrage of punches that staggered McGregor, referee Robert Byrd called the fight with McGregor looking hurt along the ropes.

Mayweather led 89-82, 89-81 and 87-83 on the judges' scorecards.

"I think we gave the fans what they wanted to see," said Mayweather, who disappointed many casual boxing viewers with a slow-paced fight against Manny Pacquiao in 2015.

"I owed them for the Pacquiao fight. I had to come straight ahead and give the fans a show. That's what I gave them. He's a lot better than I thought he'd be. He's a tough competitor, but I was the better man tonight."

Preview: What once seemed to be an impossibility is finally here. Conor McGregor and Floyd Mayweather are set to fight at T-Mobile Arena in Las Vegas, bringing together the best that MMA and boxing have to offer.

Mayweather is inarguably the best boxer of his generation, having gone a perfect a 49-0 since he turned pro in 1996. He announced his retirement after defeating Andre Berto on Sept. 12, 2015, but he’s returned to the sport for what could be the biggest money-making event in pay-per-view history.

When Mayweather left boxing, McGregor took over as the biggest star in combat sports. Three months after Mayweather called it quits, McGregor won his first title, knocking out UFC featherweight champion Jose Aldo in just 13 seconds. He went on to fight three times in 2016, winning bouts at lightweight and welterweight, helping sell more than four million PPVs.

In Mayweather, McGregor faces a challenge unlike any that he’s come up against in his professional career. The UFC lightweight champion doesn’t have a professional boxing match on his resume, and he’s taking on the top fighter of the last two decades.

The betting odds have shifted towards McGregor for months, though he has been a decided underdog throughout the entire build towards the fight. Mayweather was better than a 1/20 favorite when the bout first appeared to be a real possibility, and a victory for McGregor would be considered by many to be the greatest upset in sports history.

Floyd Mayweather Conor McGregor
Saturday's fight between Floyd Mayweather and Conor McGregor, pictured during their official weigh-in at T-Mobile Arena on Aug. 25, 2017 in Las Vegas, could come down to the judges' scorecards. Getty Images

Despite his inexperience, McGregor has guaranteed that he’ll be the one that comes out on top. Initially promising a knockout within the first four rounds, McGregor said he’d be surprised if Mayweather made it past two rounds when the decision was made to allow the fighters to use eight-ounce gloves. Going 21-3 in his professional MMA career, McGregor has 18 wins by knockout.

McGregor has been defeated as recently as March 5, 2016, and he was submitted all three times in defeat. Submissions, of course, won’t be an option for either fighter in Saturday’s boxing match.

Mayweather might be the best defensive fighter of all time, and he’s cruised to 12-round victories for much of his career. He does have 26 knockouts, though most of them came in his younger days. Mayweather hasn’t knocked out a fighter since he dropped Victor Ortiz in 2011 for his 42nd win, and that bout ended in controversy.

It’s been nearly 10 years since Mayweather scored what many fight fans would consider to be a legitimate knockout. His last knockout before that came in 2005 when he beat Sharmba Mitchell to go 35-0, though Mayweather, just like McGregor, has vowed that the bout won’t go the distance.

When Mayweather and Manny Pacquiao fought two years ago, the pay-per-view set a record with 4.6 million buys. The fight, however, didn’t live up to the hype, and Mayweather cruised to a unanimous decision in a bout that didn’t feature much action.

Will Mayweather vs. McGregor deliver?

The three judges are Burt Clements, Dave Moretti and Guido Cavalleri. Robert Byrd is the referee.

Here's how International Business Times is scoring each round of the Mayweather-McGregor fight:

Round 1

McGregor is aggressive and lands a few early punches, putting Mayweather up against the ropes. Mayweather misses a punch and McGregor taunts him by putting his hands behind his back. Mayweather is feeling McGregor out, but the UFC champ wins that round.

Mayweather, 10-9

Round 2

Mayweather starts the round in the corner, and McGregor again is the aggressor. He lands a few decent shots in the center of the ring, and without much offense from Mayweather, he takes another round.

McGregor, 10-9

Round 3

McGregor sends Mayweather to the corner again, but he’s warned by the ref for a punch in the back of the head. Mayweather has to start being more aggressive and winning rounds. McGregor is swinging wildly at times and landing a few shots. McGregor takes this one without much action from the undefeated boxer.

McGregor, 10-9

Round 4

McGregor is aggressive, but he could soon lose a point for illegal punches. McGregor looks to be getting tired, and Mayweather is finally utilizing his jab. McGregor tagged Mayweather a few times in the face, but the tide could be turning.

Mayweather, 10-9

Round 5

Mayweather is defensive to start the round, and it’s a pretty uneventful first two minutes. Mayweather takes over in the final minute, and McGregor looks to be tiring.

Mayweather, 10-9

Round 6

McGregor is the aggressor to start this round like every other round. Mayweather has a flurry of some head shots and seems to be on the verge of wobbling McGregor. This is the best round of the fight, but Mayweather has the edge. No matter what happens, McGregor is proving a lot of people wrong.

Mayweather, 10-9

Round 7

For the first time all fight, Mayweather is aggressive to start. McGregor is holding onto Mayweather a bit and showing signs of fatigue. Mayweather is tagging McGregor with the right hand, and he seems to have taken control. Perhaps his best round.

Mayweather 10-9

Round 8

Mayweather is blocking McGregor’s early punches, though he lands a sizeable shot 40 seconds in. McGregor, however, is showing some resolve. It’s one of the closest rounds of the fight, and McGregor might have done enough to steal it.

McGregor, 10-9

Round 9

McGregor hurts Mayweather early with a body shot, but the ref breaks it up and halts the UFC champ's momentum. Mayweather just covers up for the rest of the first minute, but he lands a few shots to the head 80 seconds in. McGregor is hurt, but somehow still standing after a bunch of blows to the head. McGregor might not have three more minutes left in him.

Mayweather, 10-9

Round 10

That’s it. McGregor never hits the canvas, but he doesn’t have his legs and the ref stops it after a number of blows to the head by Mayweather.

Mayweather by TKO