By Carlos Boogs

WBC/WBA welterweight champion Floyd Mayweather Jr. (48-0, 26KOs) is nearing the end of the road for his professional career.

On September 12th at the MGM Grand in Las Vegas, Mayweather will defend his world titles against two-time champion Andre Berto in the headliner of a Showtime Pay-Per-View.

Mayweather says the bout with Berto will be the final contest of his professional career.

When discussing the best thing about his longevity, Mayweather credits his defensive fighting style as being the biggest reason for lasting in the sport for 19 years and being undefeated in 48 fights.

He expects Berto to bring the drama, but don't expect Mayweather to suddenly become Arturo Gatti by engaging him in a toe to toe war.

"Being in a toe to toe battle is not a good thing. The best and coolest thing about my career - is called the sweet science. That's hitting and not get hit, making a lot of money, and leaving the sport with all of your faculties - that's the best thing about my career," Mayweather said.

"Being in hard battles and taking ass whoopings will retire you. I'm about dishing it and not taking it. I would tell every young fighter who is watching these interviews - 'don't take any punishment, be smart, and the name of the game is the sweet science, to hit and not get hit.'"