Floyd Mayweather Jr.’s victory over Andre Berto is perfect ending to plan

In the town that welcomes overindulgence, Floyd Mayweather Jr. served up 12 more rounds of his patented fighting style Saturday night in what he says will be his final fight.

In a showcase of technical boxing, superior defense and some in-ring entertainment to boot, Mayweather matched former heavyweight champion Rocky Marciano’s famed 49-0 record with a unanimous-decision victory over 18-to-1 underdog Andre Berto.

Judges Steve Weisfeld (118-110), Dave Moretti (117-111) and Adalaide Byrd (120-108) scored heavily for Mayweather in the World Boxing Council and World Boxing Assn. welterweight title bout.

Punch statistics were also one-sided, showing Mayweather connected on 232 of his 410 punches (57%) while allowing former welterweight champion Berto (30-4) to reach him on only 83.

“My experience played a big role in the fight,” said Mayweather, 38, who capped his six-fight deal with Showtime and then told a skeptical audience of 13,395 at MGM Grand that he’s also closing the book on his career.

“I’ve been in this sport 19 years. You’ve got to know when enough is enough. My record speaks for itself.

“My career’s over. It’s official.”

Except, there’s still a major opportunity to collect even more money than the guaranteed $32-million purse he earned Saturday.

MGM Grand will open a new 20,000-seat arena in April, and Mayweather’s competitive fire could get stoked by the challenge of someone like a rehabilitated Manny Pacquiao or middleweight champion Miguel Cotto, should he beat Saul “Canelo” Alvarez on Nov. 21.

Mayweather wasn’t biting on that Saturday after frustrating Berto with 83 connected jabs.

“I’m leaving the sport with all my faculties,” Mayweather said. “Still smart. Still sharp There’s nothing else to accomplish in the sport.”

It’s a rare feat for a pro athlete to leave the sport at peak performance.

Berto said he saw no slippage from the fighter who moved into a tie for third place with former heavyweight champion Joe Louis by winning his 26th title fight, behind only Omar Narvaez (28) and Julio Cesar Chavez Sr. (31).

“He was just difficult, slippery,” Berto said. “He’s real crafty, man. He’s where he is for a reason. One of the best ever, for sure. I was in great shape, but it was difficult to fight him. I tried to use my speed, but he was using little things, smart things to get me off my rhythm.”

Facing Berto was seen by many as an anticlimactic event after Mayweather beat Pacquiao by unanimous decision. The most lucrative bout in history was panned by fans who spent $100 for the pay-per-view and were treated to little toe-to-toe action.

Mayweather promised more activity in this one and he was his sharp old self immediately, landing a series of lefts, including a hard one to the face in the first round while remaining out of Berto’s reach.

The champion’s jab began to shine in the second, scoring points with the judges as Berto flailed.

Mayweather rushed Berto to start the third and hit him in the face with a right. In the fourth, Mayweather wobbled the challenger with a clean right to the head.

In the seventh, Berto tried five straight punches that hit only air, and after Mayweather whipped Berto in the face with a left, he mocked the charging challenger, staying away before hitting him with two jabs and a right.

In the corner later, Mayweather Jr. complained to his father/trainer, Floyd Mayweather Sr., that his left hand hurt.

When asked afterward about it, he said, “It doesn’t matter if I hurt my left or right hand, my career is over.”

Yet, he sought to entertain the crowd before his Saturday exit, engaging in a 10th-round trash-talking session with Berto that grew so intense that referee Kenny Bayless had to stop the fight to tell them to muzzle it.

In the 11th, Mayweather kept outboxing Berto, talking to friends in ringside seats before urging on the crowd’s cheering by waving his arms upward, smiling widely.

He opened the 12th by battering Berto with a right-left-right combination, held up his right arm in victory and then postured toward a neutral corner as the clock expired.

lance.pugmire@latimes.com