The fight is scheduled for September 14 at MGM Grand, says 36-year-old fighter on Twitter.
Boxing: Floyd Mayweather announces Alvarez fight on Twitter
Floyd Mayweather will fight young Mexican star Canelo Alvarez on September 14 at the MGM Grand.
"I chose my opponent for September 14th and it's Canelo Alvarez," Mayweather said on Wednesday night on Twitter. "I'm giving the fans what they want. It will be at the MGM Grand."
Alvarez sent a tweet in Spanish announcing the fight.
The 36-year-old Mayweather is unbeaten in 44 fights, the last a unanimous 12-round decision over Robert Guerrero on May 4 at the MGM Grand in defence of his WBC welterweight title fight.
Alvarez is 42-0-1. The 22 year old unified the WBC and WBA super welterweight titles April 20 in San Antonio with a unanimous victory over Austin Trout.
The fight will be contested at a catch weight of 69kgs and offers a rare bout between two unbeaten fighters in their primes.
"Floyd has said from Day 1 that he wants to give fans the best fight out there and here it is," Mayweather's co-manager, Leonard Ellerbe, told the AP. "We have the two biggest stars in the sport and they're fighting each other September 14."
The bout will be the second in Mayweather's six-fight, 30-month contract with Showtime that could pay him more than US$200 million (Dh734m).
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