LAS VEGAS — By the look of things, retirement was treating Floyd Mayweather Jr. well.

He had a stable of boxers to promote, businesses, including a new strip club, to run, and a vast collection of luxury cars to enjoy. But there is a reason he embraces the nickname Money: His brand was built as much on personality and spectacle as on skills in the boxing ring.

So when a rivalry with the mixed martial arts star Conor McGregor was manufactured on social media, Mayweather, 40, was more than happy to end his two-year retirement and to collect one final, potentially record-breaking paycheck. And he did it in the style that virtually everyone expected.

After allowing McGregor — 29 and boxing professionally for the first time — to come at him early in the fight with awkward punches that were by turns slapping and sharp, Mayweather took control in the middle rounds. He never looked back. He reddened McGregor’s face with a barrage of right-handed bombs, leading the referee to stop the fight a little more than a minute into the 10th round on Saturday night at T-Mobile Arena. The victory left Mayweather with a 50-0 record as a boxer, and dropped McGregor’s mark to 0-1.