Floyd Mayweather has won a 12-round majority decision over Marcos Maidana to extend his perfect record to 46-0 in a welterweight world title unification bout.

The 27-year-old American retained his World Boxing Council world title and took Maidana’s World Boxing Association belt, winning Saturday night’s fight in Las Vegas with scores of 117-111 and 116-112 while the third judge scored it 114-114.

An 11-1 favourite heading into the fight, Mayweather did not get the decisive victory that so many had predicted as the more aggressive Maidana gave him all he could handle.

Argentina’s hard-punching Maidana, who was making the first defence of his title, suffered the fourth loss of his career to go with 35 victories.