By Ryan Burton

Over the past month Floyd Mayweather Jr. has hinted at a return to the ring to go after his 50th win which would break Rocky Marciano's perfect 49-0 mark.  Insiders and fans alike wouldn't be surprised if returned to the ring but what was surprising was that he was looking to face MMA star Conor McGregor.

Mayweather went as far as to tweet a photo of a fight poster for the mythical bout, with a September pay-per-view date on Showtime.  All of the talk stopped (for now at least) when the UFC announced last Saturday after UFC 199, that McGregor would face Nate Diaz in a rematch on August 20th at UFC 202.

BoxingScene.com recently spoke with WBA welterweight champion Keith Thurman, who has longed for a fight against Mayweather for quite some time, to get his opinion on the potential Mayweather-McGregor crossover fight.

"Floyd Mayweather is always trying to sell a product - which is Mayweather versus anybody. He is really trying to excite the crossover which really is very interesting because we have never had an MMA crossover. We've had boxers crossover into MMA but you have never had an MMA figure crossover into boxing and the reason probably is because they limit their abilities to win. They are two different sports," Thurman told BoxingScene.com.

"If you are used to using your hands and your feet, stand up and ground game and now all of a sudden you can only use your stand up and hands it is a completely different kind of fight. Twelve 3-minute rounds. It is a lot longer duration than five 5-minute rounds. Statistically and mathematically Conor McGregor and Mayweather have no business being in the ring against one another besides the fact that they may want to amp it up and hype it up and try to create a business out of it which is what I think they are really trying to do."

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