By Ryan Burton

LAS VEGAS - In what is expected to be the final fight of his illustrious 19-year career, boxing superstar and pound-for-pound king Floyd "Money" Mayweather (48-0, 26 KOs) will put his undefeated record and WBC and WBA Welterweight World Championships on the line against power-punching, two-time welterweight world champion Andre Berto (30-3, 23 KOs) Saturday, Sept. 12 at the MGM Grand Garden Arena in Las Vegas, live on SHOWTIME PPV (8 p.m. ET/5 p.m. PT).

In what is expected to be the final fight of his illustrious 19-year career, boxing superstar and pound-for-pound king Floyd "Money" Mayweather (48-0, 26 KOs) will put his undefeated record and WBC and WBA Welterweight World Championships on the line against power-punching, two-time welterweight world champion Andre Berto (30-3, 23 KOs) Saturday, Sept. 12 at the MGM Grand Garden Arena in Las Vegas, live on SHOWTIME PPV (8 p.m. ET/5 p.m. PT).