Is Floyd Mayweather v Conor McGregor a serious prospect?

With a recent report claiming the two headliners were discussing a fight, Mayweather advanced the speculation on the sidelines of the Canelo Alvarez and Amir Khan clash in Las Vegas at the weekend.

"It's possible. It's possible. There was a name that was shot at me," Mayweather told FightHype.com. "But the rumours that y'all have been hearing (are) the rumours I started. It may not be a rumour. Keep your fingers crossed."

The 39-year-old American retired last September after accumulating a 49-0 record during a 19-year career that produced world titles in five weight divisions and earnings in excess of $800 million.

He has hardly faded from the scene, however, and Mayweather appeared at ringside following boxer Adrien Broner's victory over Ashley Theophane last month.

Broner then verbally challenged Mayweather, who laughed off that taunt but he did recently allude to a comeback in an interview with Showtime, bringing along with it whispers of a possible rematch against Manny Pacquiao.

Dubbed 'The Fight of the Century' by promoters, their long-awaited showdown on May 2 last year was a disappointing affair, as Mayweather easily outpointed his Filipino opponent in a low-key and ultra-defensive encounter.

However, one more win would put Mayweather ahead of heavyweight great Rocky Marciano, who also retired with a perfect 49-0 career record.

"It's not important," Mayweather told FightHype.com of the record. "I didn't let a sport retire me. I was able to retire from a sport and quit on my own terms."

UFC featherweight champion McGregor was dropped from his rematch against welterweight Nate Diaz at UFC 200 in July for refusing to attend a news conference to promote the event.

McGregor, who was choked into submission in a non-title bout against Diaz in March, subsequently hinted that he could retire before making an aborted attempt to get back on the card.

In response to speculation about a possible meeting with Mayweather, the Irishman tweeted a mock promotional poster of the two fighters face-to-face with the caption "MMA Vs Boxing."

You can never rule anything out where Mayweather is concerned especially when he is being offered huge sums of money, but this sounds ridiculous in the extreme, more like a public relations stunt by both men via a salivating social media. The prospect of Mayweather earning $144m - the sum which has been touted by The Sun newspaper for a prospective bout with McGregor - will appeal more to 'Money' than the standard of his opponent. But you would have to suggest the possibility of this coming off sounds far-fetched. A bit like the time Rocky Balboa met Hulk Hogan in Rocky III.

Not least because boxing and MMA are two vastly different disciplines. Who would sanction it? Where would it be staged? What weight would they fight at? McGregor is not a boxer. Which is the biggest problem. And Mayweather isn't going to take up MMA. What we should take from Mayweather's weekend comments is that his latest retirement is merely temporary, and you wonder how interested he would be in another meeting with a figure such as Canelo Alvarez after the Mexican's brutal sixth-round KO of Amir Khan in Las Vegas. Mayweather will fight a boxer if and when he fights again.