LOS ANGELES — Floyd Mayweather Jr. is a champion boxer and has tested his moves on "Dancing With the Stars." Now the man many consider the best pound-for-pound fighter in the world is preparing to drop the gloves and do some wrasslin.'

A $20 million payday awaits the undefeated WBC welterweight champion when he takes on Big Show as part of WWE's "WrestleMania XXIV" at Citrus Bowl in Orlando, Fla., on March 30.

"It's entertainment. You have a chance to just be you and do what you want to do," Mayweather said today after a chaotic Staples Center event that masqueraded as a news conference.

The boxer nicknamed "Money" clearly likes the way WWE does business.

"Wrestling takes care of business right on the spot," Mayweather said. "Whatever they say they're going to do, they do it right on the spot. There's no waiting three, four, five months. Quick results, quick money. Quick big money, too."

His manager Leonard Ellerbee and WWE executive Shane McMahon confirmed Mayweather's eight-figure payday for the outdoor match to be shown on live on pay-per-view.

Mayweather incited the couple hundred of already hyped fans at Staples Center by whipping out a thick wad of cash and repeatedly tossing $100, $50 and $20 bills into the crowd that had nearly as many women as men.

A mad scramble ensued, with a light pole nearly getting knocked over and two small children caught in the chaos. One lucky man emerged from the pileup clutching six $100 bills.

Mayweather played to the frenzied crowd after appearing from behind a black curtain wearing a New York Yankees jacket and cap. Fans shouted insults and the name of hometown hero Oscar De La Hoya at Mayweather.

"I run Vegas and I run L.A. and I will run the WWE," he boasted.

At 5-foot-8, 150 pounds, Mayweather gives up big numbers to the bald Big Show, who stands 7-feet and weighs 430.

"I weigh three times as much as he does," Big Show crowed. "It's not fair, but I'm a businessman and I see an opportunity for business."

Then he picked up the wooden podium and tossed it to the floor, where it splintered and the attached two mics lay like broken sticks. Clearly, Staples Center officials hadn't expected the move.

Mayweather hopped onto a chair and exchanged glares with Big Show while WWE regulars Randy Orton, John Cena, Triple H and Edge looked on, witnessing a newcomer who clearly understands the theatrics of modern-day wrestling.

"WWE is the biggest it gets," Mayweather said. "This is going to be an event like none other."

Ellerbee scoffed that hard-core boxing fans won't take Mayweather seriously after his WWE antics.

"After March 30, when Floyd goes out and takes care of his business at WrestleMania, he's still going to be the best fighter in the world and the face of boxing," he said. "Tell me what changes about that? Nothing changes."

The wrestling gig is another part of Ellerbee's carefully crafted plan to expand Mayweather's fan base.

"Either I'm going to be a genius with this or I'm the biggest idiot," he said. "Boxers have such a short window of opportunity. He can't become any bigger in boxing."

That's why Ellerbee snagged Mayweather a spot on ABC's reality hit "Dancing With the Stars." Mayweather didn't win the disco ball trophy, but he wasn't the first one voted off, either.

"It crossed him over and took him into the households of many middle-aged Middle Americans and turned him into a mainstream superstar," Ellerbee said. "Now when Floyd goes into the grocery store, the first thing 65-year-old ladies say is, `You're Floyd from `Dancing With the Stars."'

Mayweather plans to train with WWE Latino star Ray Mysterio, who wears a mask on his face.

"I'm outside the box," he said, lapsing into the third person. "Floyd Mayweather is not just a fighter, he's an entertainer. That's what the world must know."

But he hasn't forgotten his night job.

Mayweather alluded to a possible rematch with De La Hoya in September. De La Hoya lost a split decision in their last bout May 5.