Floyd Mayweather Jr. announced on Wednesday that he will next fight Canelo Alvarez.  The two will meet on Sept. 14 for the WBA/WBC super welterweight titles at the MGM Grand Garden on Showtime PPV, Yahoo! Sports report.

"I choose my opponent for September 14th and it's Canelo Alvarez," Mayweather tweeted Wednesday night. "I'm giving fans what they want. It will be at the MGM Grand."

Mayweather confirmed last month that he chooses his own opponents. While it wasn't necessarily a surprise, he did receive a fair share of criticism. He defeated Robert Guerrero, a fighter who moved up in weight for the bout, last month in a unanimous 12-round decision.

Choosing Alvarez, however, wasn't picking the easiest path to staying undefeated. Alvarez, unlike Guerrero, is a natural super welterweight. He's 42-0-1, and he's 13 years younger than Mayweather.

Alvarez, who will turn 23 in July, is widely considered a top 20 pound-for-pound fighter. He's coming off an impressive win over Austin Trout and, like Mayweather, Alvarez is a major box-office draw.

Leonard Ellerbe, Mayweather's co-manager, claimed it impossible for any active fighter to beat his client. Alvarez will give Mayweather, 36, a real run for his money at keeping undefeated.

Mayweather returned to the ring against Guerrero with a renewed emphasis on defense. He resumed training with his father, who had been his longtime trainer. Together they focused on his defense, which at times frustrated Guerrero and saved Mayweather from hits. Their philosophy was the less Mayweather gets hit, the longer his career.

The Mayweather-Alvarez fight will have a 152-pound weight limit, and it offers a rare fight between two fighters in their primes. It will be Mayweather's second of six fights that he signed to do with Showtime, which could pay him in the end more than $200 million, according to the Associated Press.

"Floyd has said from Day 1 that he wants to give fans the best fight out there and here it is," Ellerbe told AP reporters. "We have the two biggest stars in the sport and they're fighting each other Sept. 14."