Alvarez's deal includes 11 fights on DAZN, a global live-sports streaming service, beginning with his next fight: December 15 at Madison Square Garden against Rocky Fielding for the WBA super middleweight world title.
Its early success across Europe and Asia was followed by launches in Canada (2017), Italy (2018) and the United States (2018), where DAZN announced blockbuster deals with Matchroom Boxing and Bellator MMA to deliver a stacked slate of fight sports content upon entry into the market.
This appears to be a totally separate deal according to Rafael's report however, where Golden Boy look to be planning to make DAZN their new home for boxing.
Although Hearn was not involved in the deal to bring Alvarez to DAZN, the move is intriguing for the middleweight division if the pound-for-pound star - who has only lost to Floyd Mayweather - returns to 11st 7lb next year. He will meet secondary world champ Rocky Fielding on December 15 at Madison Square Garden in NY.
"Canelo is the highest-paid athlete in the world".
"We are thrilled to be exclusive partners with Golden Boy Promotions and Oscar De La Hoya", said John Skipper, DAZN Group Executive Chairman.
The reported value of the deal would top the previous most-valuable contract - the $325m 13-year deal of baseball star Giancarlo Stanton in 2014.
Rocky Fielding says a stunning upset win over Saul "Canelo" Alvarez would make him "the King of NY and the new face of boxing".
The Mexican's only professional loss came against Floyd Mayweather in 2013. The deal is with sports streaming service DAZN and means an average take of $33 million per fight.
"This is only from my hard work", said Alvarez, speaking to ESPN after signing the contract. Right now, Canelo Alvarez is the most important fighter in pay-per-view. "Being part of this historic deal will require me to prepare myself even more and offer fans even better performances".
"It is a good factor in some ways - but I know he is an all-around complete fighter".
"I always want to take on challenges, and I am very happy my fans will be able to see me fight for a small cost".
Golovkin, who was also with HBO, has not agreed a deal with a new US TV network yet and his move could signal how likely he is to have a third fight with Alvarez in the near future.
Alvarez, 28, is from Mexico.
Alvarez (50-1-2, 34 KOs) beat Gennady "GGG" Golovkin in a majority decision in September to become the WBC, WBA, Lineal and Ring Magazine Middleweight champion.