Two-weight world champion Saul "Canelo" Alvarez has agreed a record-breaking 11-fight deal with sports streaming service DAZN that is the richest contract ever signed by an athlete.

The 28-year-old Mexican, who improved his record to 50-1-2 with a majority decision victory over Gennady Golovkin in September, is stepping up to the 168-pound division to fight WBA super middleweight world champion Rocky Fielding in New York City's Madison Square Garden on December 15.

That will be the first of Alvarez's next 11 bouts that will be shown on DAZN, which has also agreed a deal with Golden Boy Promotions to stream 10 fight nights per year from the start of 2019.

The 11-bout deal is "worth a minimum of $365 million," ESPN.com reported. If accurate, Alvarez's deal is the richest athlete contract in sports history, eclipsing the 13-year, $325 million agreement that Yankees slugger Giancarlo Stanton signed in 2014 when he was with the Marlins.

Alvarez has won world titles at middleweight and light middleweight in his career and has recorded victories over the likes of Golovkin, Amir Khan, Miguel Cotto and Shane Mosley.

"I've always liked a challenge, and this is yet another challenger in my career," said Alvarez.

"Being part of this historic deal will require me to prepare myself even more and offer fans even better performances.

"At the same time, I am humbled to be selected to lead this new vision for the sport of boxing, which will without a doubt be for the benefit of the fans."

Golden Boy Promotions chairman Oscar De La Hoya added: "This is easily one of the best days in the growing history of Golden Boy Promotions.

"We are committed to making this sport as accessible as possible and at an affordable price for all the fans. My dream has been to make boxing a sport for all.

"DAZN has the perfect platform to make this dream come true, and with the biggest star in the sport at the helm of this journey, I have no doubts that we will succeed in unimaginable ways."