LAS VEGAS – Floyd Mayweather dropped to his knees as the final bell sounded after his whitewashing of Andre Berto on Saturday and looked skyward.

For the final 30 seconds, the crowd of 13,395 at the MGM Grand Garden stood, their camera phones in their hands, documenting the end of the unbeaten star’s legendary career.

Berto offered little in the way of a serious challenge and Mayweather cruised to an easy victory, running his record to 49-0 in what he insists will be his last fight.

Few believe he’ll be able to stay retired, but he earned at least another $32 million and, with television upside, his 2015 earnings could push past $300 million.

He again insisted his career was over, and while he didn’t always fight the way many fans wanted, he leaves the sport with his faculties intact and hundreds of million in the bank.

“You’ve got to know when it’s time to hang it up, and it’s my time to hang up,” Mayweather said. “I’ve been in the sport 19 years and been a world champion for 18. I have nothing else to prove in the sport of boxing.”

He told his father, Floyd Sr., following the ninth round that he injured his left hand, but dismissed it later.

“It doesn’t matter if I hurt my left hand or my right hand,” Mayweather said. “My career is over.”

The fight was like so many of the 48 Mayweather bouts that preceded it. Berto simply wasn’t good enough to force Mayweather to fight and so Mayweather fought at his range and at his pace. Mayweather pounded Berto with his jab, did a nice job going to the body and largely controlled the action.

Mayweather seemed to hurt Berto twice, but there were no knockdowns and no classic back-and-forth exchanges. Mayweather was, yet again, a defensive master, and made it impossible for Berto to hit him.

Berto landed just 17 percent of his punches, while Mayweather connected on an astounding 57 percent (232 of 410).

“He was difficult to hold onto and was slippery, very slippery,” Berto said. “Like I said, experience played a big part. I tried to use my speed, but he was using little things, smart things, to get me off my rhythm. I was coming, but he was crafty. He had a lot of speed and is very crafty.”

Mayweather, who made about $250 million in May when he defeated Manny Pacquiao in what was billed as “The Fight of the Year,” has insisted since this fight was announced that he’d retire.

Few believed him, or believe him now. The MGM is opening a new 20,000-seat arena in May, and Mayweather would break Marciano’s long-standing mark if he fought and won once more.

There would be no shortage of huge paydays if he chose to reconsider, but he said he’s made more than $700 million in his career and is looking forward to spending time with his children.

“I’m financially secure and I’m in good health,” he said. “I’m looking forward to finding the next Floyd Mayweather and seeing someone break all these records I set.”

The crowd briefly chanted “TBE! TBE!” during the fight, referring to Mayweather’s self-annointed moniker of “The Best Ever.”

Most boxing historians consider Sugar Ray Robinson the best fighter ever, and Berto, despite getting walloped, wasn’t about to put Mayweather in that company.

He chuckled when he was asked if he believes Mayweather is the best fighter ever. He thought for a second and then send, “He’s definitely one of the best out there.”

And now, apparently, he’s done.

The search for the next superstar is officially on.