Floyd Mayweather Jr. admitted that he personally picks every opponent he fights. He also controls the details of both his and his opponent's contracts, including how much each fighter earns. 

Yet the biggest surprise is the clause that Mayweather put in the contract of his next opponent, welterweight Robert Guerrero.

"He asked for a rematch clause. That was the very first thing," Robert Guerrero said. "It just shows where his head is at."

Contracts don't often have rematch clauses. If Mayweather is worried about losing, he isn't showing it.

"I've done this my whole life," he said. "This is what I love to do."

At 36-year old, Mayweather, is entering the twilight of his career. It's the age most boxers struggle with, according to the Associated Press.  He is unbeaten in his 43 fights, but age will inevitably catch up to him and slow his body.

Rust could also be an issue. His last fight was in May 2012 in a victory over Miguel Cotto by a unanimous decision.

Mayweather can still draw a crowd. He has a new six-fight television deal that will likely make him the world's highest paid athlete. Guerrero and Mayweather will fight next year. Guerrero isn't concerned that Mayweather handpicked him.

"They talk about this as Floyd Mayweather's home," Guerrero said. "Well, this is a home invasion."

He is confident he can become the first to hand Mayweather a defeat. Guerrero is a former champion in three different weight classes and boasts a record of 31-1-1. The Californian native is anxious for the biggest fight of his career.

"The only thing that means something is what you do in that ring," he said. "I just can't wait to get in that ring."

Tensions continue to build between the fighters. Mayweather has called Guerrero a hypocrite for facing four felony charges in New York for allegedly trying to bring an unloaded gun onto an airplane. 

Mayweather teased Guerrero's well-documented faith on Tuesday and asked, "If God's got your back, why are you carrying a gun?" 

Even the boxers' fathers, who both train their sons, almost got into a brawl at the fight's last press conference after Guerrero chided Mayweather for being a woman beater — a reference to the domestic altercation last year that gave Mayweather 70 days in jail.

The fight, still a year away, is already shaping up to be a blockbuster.