By Keith Idec

NEW YORK – Floyd Mayweather Jr. is beyond tired of discussing a boxing match against UFC superstar Conor McGregor that the boxing superstar promises will never happen.

McGregor continues to mention Mayweather as a potential opponent, even though McGregor never has participated in a professional boxing match. The story has received more attention since McGregor knocked out Eddie Alvarez in the second round Saturday night as part of UFC 205 at Madison Square Garden.

The provocative Irishman told a crowd at a New York City nightclub later Saturday night that he would require “$100 million in cash” to meet Mayweather in a boxing ring.

Mayweather (49-0, 26 KOs), retired from boxing for more than a year, came to Brooklyn on Wednesday to promote a Showtime Championship Boxing doubleheader scheduled for January 14, which will feature IBF super middleweight champion James DeGale (23-1, 14 KOs), of London, against WBC 168-pound champ Badou Jack (20-1-2, 12 KOs) in the main event. Sweden’s Jack is a member of the Mayweather Promotions stable.

“Totally false,” Mayweather said regarding a rumored fight against McGregor. “If you don’t hear it from my mouth, it’s not true. If you don’t hear it from my mouth, it’s not true. Once again, with different sports, as far as MMA and boxing, you have to realize this – Floyd Mayweather is the biggest name in MMA. Floyd Mayweather is the biggest name in the sport of boxing, and I’m not even competing anymore.

“I’m a fighter. I went out there and fought hard. I did record-breaking things and I moved on with my career. But you have guys that steady are using my last name, using Floyd Mayweather’s name, to piggyback off of my name. I think that fighters and people that compete in physical combat need to go out there and lay the groundwork and make their own name.”

The 28-year-old McGregor (21-3) became the first fighter to hold UFC championships simultaneously in two weight classes after defeating Alvarez (28-5) to win the UFC lightweight title (155 pounds). He also owns the UFC featherweight championship (145 pounds).

Mayweather, 39, retired as boxing’s WBA and WBC welterweight champion (147 pounds).

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.