Floyd Mayweather Jr has retained his WBC and WBA welterweight titles with victory over Andre Berto by unanimous points decision to extend his unbeaten record to 49 matches.

The 38-year-old was in imperious form in the contest and secured the win by scores of 117-111, 118-110 and 120-108 respectively to move level with legend Rocky Marciano to post a record of 49-0, in what he claims was the final match of his career.

Mayweather started the fight with confidence as he used his jab early to knock the 32-year-old out of his rhythm and staved off his attempts to get into close quarters by using his agile footwork.

The defending champion began to frustrate Berto with his speed and then provided a quick shot to the midsection before retreating to avoid the furious swipes of the Florida-born fighter.

Mayweather's speed proved to be too much for the 32-year-old to handle as he failed to land a telling blow as the pound-for-pound king continued to punish him with his jab.

The 38-year-old brought the heat in round six with three quick blows followed by a uppercut to take the fight away from Berto, but the former world champion responded in the seventh with his best form.

However, Mayweather restored his control of the fight as frustration crept further into the challenger's approach, which allowed the champion to evade his wild punches and land a telling uppercut to all but secure the win.

The 38-year-old ended the match by prancing around the canvas to display his dominance before the bell sounded to announce his victory.