Boxer Mayweather beats Berto in farewell bout

Floyd Mayweather Jr. cemented his place among the pantheon of boxing greats with a unanimous decision over fellow American Andre Berto on Saturday in what he has repeatedly said would be the final fight of his career.

Mayweather, 38, outboxed his younger opponent over the 12 rounds to retain his WBC and WBA welterweight titles and improve his perfect career record to 49-0, matching the benchmark set by former heavyweight champion Rocky Marciano.

Five-division world champion Mayweather dominated most of the exchanges in the MGM Grand Garden Arena with his lightning jabs and agile movement about the ring to finish ahead on all three judges' scorecards.

Berto, a 30-1 underdog against one of the best defensive fighters of all time, dropped to 30-4 as he suffered his fourth loss in his last seven fights.

Back in the ring for the first time since May when he beat Manny Pacquiao in a 'mega-fight' that became the richest bout in boxing, Mayweather landed 232 of 410 punches while Berto connected with just 83 of 495.

However, it was a welterweight showdown that failed to capture the public's imagination given Berto's relatively low profile globally and his mixed run of results over the past four years, and it was low on entertainment value on the night.

Barely five hours before the start, the MGM Grand box office said "a bunch of tickets" were still available for the arena in the price range between $300 and $1,500, but many of those were snapped up by fight time.