Will this really be it for Mayweather?

Since he's made them in the past as well, many remain skeptical about Mayweather's retirement claims

LAS VEGAS: Floyd Mayweather says he will call it quits after Saturday's welterweight world title defense against massive underdog Andre Berto in which victory would give him a perfect 49-0 record.

But boxing -- perhaps more than any other sport -- is littered with men who proclaimed they were hanging up their gloves, only to find the lure of just one more shot at the big time or one last payday too much to resist.

The unbeaten Mayweather, 38, the self-proclaimed "TBE" ("The Best Ever"), insists he will not be joining them.

Read: Floyd Mayweather,'The Best Ever', prepares to hang up gloves

But then this is not the first time that he has said he is retiring: in 2008 he also said he was done.

This time is different, he says, because he wants to get out of boxing with his health intact and he has enough money -- Forbes says he is the world's highest-paid athlete -- to avoid having to work another second for the rest of his life.

"If you stick around anything too long, anything can happen. I'm not really worried about losing, but I want to have a sharp mind. You can make a lot of money, but you still want to be able to talk, walk, and have a sharp mind," he said.

"Of course, it's always about self-preservation. I come first but I appreciate the fans. I do. The only thing I can do is believe in myself and believe in my skills. I'm going to be TBE until the day I die."

The American says now is the time to go because he has nothing more to prove.

He also says that he has plenty to occupy him after he stops fighting: he is already a boxing promoter, has his own clothes line and says he wants to develop his interests in the entertainment and music industry.

Last week, Leonard Ellerbe, CEO of Mayweather Promotions, said there had been "signficant" entertainment possibilities for the champion for when he calls it quits -- including three "major" movie offers just last week.

"I've been approached on numerous occasions (to act) but I'd rather be behind the scenes. I've had my time to shine," said Mayweather, who has spent time in jail for one of a string of domestic violence incidents.

He also has four children to watch grow up, he says.

Many are deeply skeptical of Mayweather's plans.

Read: The unbeaten and unpopular boxing champion Floyd Mayweather

"There are certain people in life who what they say really doesn't reflect all that much on what they're going to do or what they think -- and he's one of those people," said Ivan Goldman, a novelist and writer for the boxinginsider.com website.

Goldman is not alone in thinking that Mayweather -- such is his ego -- will not be satisfied with merely equaling Rocky Marciano's 49-0 record.

"I"m guessing he'll go for the magic number of 50-0," said Goldman. "Equaling a record doesn't sound like him.

"On the other hand, Floyd is very knowledgeable about fighting, he really knows.

"He understands on some level that if he keeps fighting he's going to slip and he could lose. If he takes on a rough customer next, he's going to be a few months older still."

Mayweather's vast fortune will open doors when he does finally quit, but Goldman believes his criminal past will limit his ambitions.

"They affect his life. For instance, he can't get sponsors. He can't go to Nike and get a contract with them because Nike would immediately be boycotted, so he can't do that."

Many believe the retirement talk is a cynical ploy to drum up interest in a fight with Berto that has failed to generate buzz.

"If he really, truly retires I will have a hard time lifting my jaw up off the floor," said Michael Woods, editor of The Sweet Science boxing website.

Won't the temptation to surpass Marciano's record be too much to resist?

"And let's not forget the temptation to keep on making oodles of moolah. Like, $32 million, or $50 million, or more," Woods said.