Conor McGregor 'knocked out during sparring session'

Conor McGregor's hopes of beating Floyd Mayweather have taken another hit, with rumours he was KO'd during sparring emerging.

Not many people are backing the UFC champ against Mayweather, and even fewer will be if this rumour proves to be true.

According to former WBO welterweight champion Jessie Vargas, McGregor was knocked out during a recent sparring session.

HITTING BACK: Mayweather shoots down Horn with one sentence

DISRESPECTFUL: Aussie boxer slams Mayweather-McGregor fight

"He got knocked out in sparring already," Vargas told Villainfy Mredia.

McGregor in sparring. Image: Getty

"I heard that they tried Bradley Wheeler but he knocked him out.

"The boxing world is small, it’s a small circle."

McGregor has previously been criticised over his boxing skills after the footage above emerged.

McGregor stepped into the ring with boxer Chris Van Heerden last year, but the UFC star's camp originally released a heavily edited highlights package that didn't include some pretty revealing moments.

Mayweather will put his perfect 49-0 boxing record on the line against McGregor in Las Vegas on August 26.

Mixed martial arts champion McGregor is stepping away from the octagon and into the ring with the 40-year-old American, who is regarded as one of the greatest boxers of all time.

Before they touch gloves at T-Mobile Arena, Mayweather and McGregor have been busy promoting the highly-anticipated bout in Los Angeles, Toronto, New York and London – both fighters exchanging taunts and expletives throughout their public appearances.

with AAP