Bernard Hopkins, one of the most successful boxers of the past thirty years, has angrily claimed that Conor McGregor’s upcoming showdown with Floyd Mayweather is a “fake news fight”, and insisted that the MMA star should never have been granted a boxing license.

The fight between the two men is expected to become the most lucrative in the history of the sport, despite the fact that McGregor has never before been involved in a professional boxing match.

In contrast Mayweather is widely regarded as one of the greatest ever boxing champions, with a flawless professional record of 49-0. In his celebrated 21-year career, he has been knocked to the canvas just once.

And Hopkins, who held multiple world titles at middleweight and light heavyweight during his career, has said that he feels offended a complete novice of the sport stands to earn over $100m from the contest.

“This is all fake news,” the 52-year-old, who last fought in December, told Boxing Scene.

“First of all, he hasn't fought an amateur fight to my knowledge. I've checked around and I've been around the game for a long time.

“He hasn't had any experience as an amateur or a professional. How does any commission, in Vegas or anywhere, give him a license to fight a guy like Mayweather, who is one of the icon guys of our era? How does he get that chance?”

Mayweather vs McGregor: From trash-talk to super-fight Show all 18 1 /18 Mayweather vs McGregor: From trash-talk to super-fight Mayweather vs McGregor: From trash-talk to super-fight 00-mayweather-mcgregor-trash-talk-timeline.jpg NEW YORK, NY - NOVEMBER 10: UFC Featherweight Champion Conor McGregor addresses the media during the UFC 205 press conference at The Theater at Madison Square Garden on November 10, 2016 in New York City. (Photo by Michael Reaves/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 01-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 02-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - MAY 02: Floyd Mayweather Jr. reacts after the welterweight unification championship bout on May 2, 2015 at MGM Grand Garden Arena in Las Vegas, Nevada. (Photo by Al Bello/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 03-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 04-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 05-mayweather-mcgregor-trash-talk-timeline.jpg Picture shows an arrangement of copies of The Sun newspaper front pages on February 13, 2012. Rupert Murdoch's British tabloid The Sun condemned police raids against its journalists as a "witch-hunt" worthy of former communist states, and won rare support from rival newspapers. AFP PHOTO / LEON NEAL (Photo credit should read LEON NEAL/AFP/Getty Images) AFP/Getty Images Mayweather vs McGregor: From trash-talk to super-fight 06-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - AUGUST 20: Conor McGregor waits for the start of his welterweight rematch against Nate Diaz at the UFC 202 event at T-Mobile Arena on August 20, 2016 in Las Vegas, Nevada. McGregor won by majority decision. (Photo by Steve Marcus/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 07-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - SEPTEMBER 13: Floyd Mayweather Jr. looks on while taking on Marcos Maidana during their WBC/WBA welterweight title fight at the MGM Grand Garden Arena on September 13, 2014 in Las Vegas, Nevada. (Photo by Al Bello/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 08-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - JUNE 02: Mayweather Promotions CEO Leonard Ellerbe introduces honoree Floyd Mayweather Jr. during the 2017 Southern Nevada Sports Hall of Fame induction ceremony at the Orleans Arena on June 2, 2017 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 09-mayweather-mcgregor-trash-talk-timeline.jpg TORRENCE, CA - FEBRUARY 24: UFC featherweight champion Conor McGregor speaks during an interview after a news conference with lightweight contender Nate Diaz at UFC Gym February 24, 2016, in Torrance, California. (Photo by Kevork Djansezian/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 10-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - MAY 02: Floyd Mayweather Jr. throws a left at Manny Pacquiao during their welterweight unification championship bout on May 2, 2015 at MGM Grand Garden Arena in Las Vegas, Nevada. (Photo by Al Bello/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 11-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS, NV - MAY 02: Floyd Mayweather Jr. looks on during the welterweight unification championship bout against Manny Pacquiao on May 2, 2015 at MGM Grand Garden Arena in Las Vegas, Nevada. (Photo by Al Bello/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 12-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 13-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 14-mayweather-mcgregor-trash-talk-timeline.jpg NEW YORK, NY - MARCH 17: (L to R) Conor McGregor, & Michael Conlan celebrate Conlan's 3rd round TKO win over Tim Ibarra in his super bantamweight bout at The Theater at Madison Square Garden on March 17, 2017 in New York City. (Photo by Ed Mulholland/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 15-mayweather-mcgregor-trash-talk-timeline.jpg NEW YORK, NY - NOVEMBER 10: UFC Featherweight Champion Conor McGregor addresses the media during the UFC 205 press conference at The Theater at Madison Square Garden on November 10, 2016 in New York City. (Photo by Michael Reaves/Getty Images) Getty Images Mayweather vs McGregor: From trash-talk to super-fight 16-mayweather-mcgregor-trash-talk-timeline.jpg Mayweather vs McGregor: From trash-talk to super-fight 17-mayweather-mcgregor-trash-talk-timeline.jpg LAS VEGAS - MAY 23: Musician Musician Keith Urban performs onstage during the 41st Annual Academy Of Country Music Awards held at the MGM Grand Garden Arena on May 23, 2006 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images) Getty Images

Hopkins has also hit out at Mayweather for taking the fight. Despite almost every boxing expert and personality tipping Mayweather to win comfortably – and despite the odds of a Mayweather victory being as short as 1/9 – Mayweather has repeatedly insisted it will be a competitive contest.

“That shows you the lack of respect that he has for the sport,” Hopkins said of the undefeated American.

Mayweather v McGregor: Tale of the tape