Mike Tyson

UFC champion McGregor will step out of the octagon and into the ring to fight unbeaten boxer Mayweather in Las Vegas on August 26.

Many have weighed in on who will win the hyped fight and now Tyson has voiced his opinion as Mayweather puts his perfect 49-0 record on the line against the unproven Irishman.

"McGregor is going to get killed boxing," Tyson told Barstool Sports on Monday. "Boxing? I got mad because I thought they were going to use MMA rules against boxing because that's what it's all about: Can the boxer beat the MMA guy?"

One of the most feared men in the history of the sport, Tyson had a troubled upbringing in Brooklyn, New York, before going on to become the youngest boxer to win the world heavyweight title at 20-years-old.

While much is known about his rough childhood, which included involvement in petty crime and regular stints at reformatory schools, he has revealed even grimmer details about what he went through at a young age.

Joshua, 27, knocked out Wladimir Klitschko in May to add the WBA title to the IBF strap he already held.

But Tyson - a two-time world heavyweight champion - has warned the position can be "a crown of thorns".

In a wide-ranging interview with BBC Radio 5 live boxing's Mike Costello, Tyson outlined his belief in Joshua's ability, gave his views on a potential Floyd Mayweather-Conor McGregor bout and offered insight into the man who turned him into the youngest heavyweight champion in history.

Joshua retained his IBF heavyweight title and claimed the vacant WBA and IBO straps with an 11th-round stoppage of Klitschko in front of 90,000 fans at Wembley.

The Briton sent Klitschko to the canvas in the fifth round but appeared set for defeat after the Ukrainian knocked him down a round later.

However, the unbeaten Joshua recovered and hit Klitschko with a penultimate-round barrage that sent the 41-year-old to the deck twice more before the referee called a halt to an enthralling contest.

The former heavyweight champion was asked to help out by 50 Cent after some major beef between the pair over the last few weeks.

"I'm gonna teach him how to bite somebody's ear. Yeah, that's right," he said in a video on Instagram.

"I'm gonna teach him every dirty trick in the book to knock you out. Because I'm not going to teach him how to run."

Soulja Boy is going to be trained by another former boxing champ, Floyd Mayweather, who announced the bout on Instagram.