Industry rumors have exploded that a deal is close to being finalized for Conor McGregor's cross-sports boxing match against Floyd Mayweather, after multiple outlets revealed that Mayweather Promotions placed a hold on the MGM Grand in Las Vegas for August 26.

The undefeated five division champion - who fought at the famous casino venue for the final dozen bouts of his career - came out of retirement in April to face UFC lightweight champion McGregor under boxing rules. Mayweather, now 40 years old, retired from the sport in September 2015 after dominating Andre Berto over twelve rounds at the MGM.

Last month, the Irishman has struck a deal with the UFC and company president Dana White to allow him to compete in the one-off megabucks event.

Talks between Mayweather's adviser Al Haymon and the UFC are ongoing but Mayweather has been pictured sparring , suggesting his preparations are well underway.

McGregor took to social media on Sunday, advising his followers that something very big was on the horizon and used the hashtag of "BP"= which many believe stands for 'big payday.'

Besides placing a hold on the venue for August 26th, Mayweather's promotional company has also reserved the arena on August 25 for a weigh-in.

The main event and the unannounced undercard fights the following evening will be carried on pay-per-view as part of a joint effort by UFC and Showtime, Mayweather's long-time broadcaster of choice.

Fighters from the Las Vegas resident's stable are expected to feature on the undercard, including Badou Jack, who could face WBA world light-heavyweight champion Nathan Cleverly. And a voluntary defense by IBF super featherweight champion Gervonta Davis.

McGregor, who has not fought since he won the UFC lightweight title last November, recently became a father for the first time. He has never boxed professionally having switched to mixed martial arts as a youngster.