Floyd Mayweather agrees to fight Canelo Alvarez in mega-showdown on Sept. 14 in Las Vegas

Floyd Mayweather and Canelo Alvarez agreed to terms late Wednesday to fight in a WBA/WBC super welterweight unification bout. The match will be held at a maximum weight of 152 pounds and will be at the MGM Grand Garden in Las Vegas.

Showtime will distribute the pay-per-view.

The bout is, arguably, the most significant that can be made from a pay-per-view standpoint. Golden Boy Promotions CEO Richard Schaefer said he thinks the fight has a chance to surpass the 2.5 million sales that Mayweather and Oscar De La Hoya generated in 2007 to set the record.

Mayweather, 36, will be fighting just four months after a 12-round decision over Robert Guerrero on May 4. Mayweather hasn't fought twice in a four-month period since 2001, when he met Diego Corrales on Jan. 20 and then fought Carlos Hernandez on May 26.

"Floyd wanted to give the fans what they wanted to see and this is the fight the fans and the media were calling for," said Leonard Ellerbe, the CEO of Mayweather Promotions. "Nobody believed him, but Floyd stood up there [at the podium at the post-fight news conference after the win over Guerrero] and told everyone he'd be back in September.

"Canelo is a good young fighter, but he's bitten off more than he can chew. Floyd said, 'I'm going to whip that ass.' This is a whole other level we're talking about."

Asked if he saw any way that Mayweather could lose, Ellerbe said, "Impossible."

[Related: Can Floyd Mayweather Jr. be considered an all-time great?]

Alvarez, who will be 23 in July, is unbeaten like Mayweather, though he has one draw blemishing his record. Mayweather is a perfect 44-0, while Alvarez is 42-0-1 with 30 knockouts. He respects Mayweather, but said he won't be intimidated and thinks he'll win.

"He's a great fighter, but I have intelligence in that ring and I have the same speed he has," Alvarez said through interpreter Eric Gomez. "I can use my head, but I have that special thing: I have some power that will help me."

Ellerbe said Mayweather was always focused on making a deal with Alvarez and said no other opponents had been discussed.

Top Rank president Todd duBoef said he will move his fight card featuring a super lightweight title match between Juan Manuel Marquez and Timothy Bradley Jr. – originally planned for Sept. 14 at the Thomas & Mack Center in Las Vegas – to Oct. 14 so as not to conflict with the Mayweather-Alvarez fight.

Also, the LVH sports book in Las Vegas opened Mayweather as a slightly better than 2-1 favorite. It has Mayweather at minus-250 and Alvarez at plus-210.

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