LAS VEGAS - He claims to be more mature now, chastened by a stint in jail and eager to be just as much a businessman as a fighter. Indeed, Floyd Mayweather Jr. acted almost statesmanlike earlier this week when Robert Guerrero's father began screaming that he was a woman beater who would finally get beaten himself Saturday night.

"The fighters are the ones who fight, not the fathers," Mayweather said calmly.

If it's an act, it's a pretty good one. Armed with a new six-fight television deal with Showtime that should keep him the world's highest paid athlete, Mayweather has for the most part taken the high road while promoting his fight against Robert Guerrero as must-see TV for anyone who has an extra $69.95 for the pay-per-view.

Mayweather (43-0, 26 knockouts) weighed in at 146 pounds on Friday. Guerrero (31-1-1, 18 KOs) checked in at the weight-class limit of 147.

The two meet in a scheduled 12-round welterweight-title match at the MGM Grand hotel in what will be Mayweather's first fight in a year. It's also his first ring appearance since serving a jail term for assaulting the mother of his children, an experience he said helped him grow up.

He's also an aging fighter at 36, having spent most of the past year doing pushups in solitary confinement in a small cell in downtown Las Vegas.

Sometimes, though, he just can't help himself. The old Mayweather surfaces, complete with the bad-boy persona that has made him the biggest draw in boxing.

It could be that Mayweather as the promoter is trying to give a fight that still hasn't sold out some much-needed buzz. More likely, though, is that he's looking for a bit of a mental edge for a bout that, despite the odds, could be very competitive.

He called Guerrero a hypocrite for promoting himself as a devout Christian, and then getting arrested on gun charges in New York. He mocked him for bringing up his jail sentence when he may be facing one himself.

And a few days before the fight, he even accused Guerrero of trying to win fans by using his wife's leukemia - which she overcame with a bone-marrow transplant - as a way to get sympathy.

"I'm glad she was able to beat leukemia, which is a great thing," Mayweather said. "But they keep selling the same story. It's time to talk about something different."

Rosado on the undercard. North Philadelphia's Gabriel Rosado (21-6, 13 KOs) will be the underdog against J'Leon Love (15-0, 8 KOs) in a 10-round middleweight bout before the Mayweather-Guerrero fight.