Conor McGregor has not been breaking the rules in his sparring sessions, Hall of Fame referee Joe Cortez has stated.

Cortez was appointed by McGregor's team to oversee his build-up to the bout with Floyd Mayweather this weekend.

McGregor's former sparring partner Paulie Malignaggi and Mayweather both believed that 'Notorious' had been fouling after seeing footage of his fights.

Malignaggi also said that Cortez deducted points from the two-weight UFC champion during their rounds.

However, the American referee has been quick to falsify those claims.

When questioned whether McGregor had broken the rules, Cortez said: "Very little. And it was not intentional. He knows the rules 100 per cent.

"He abides by the rules very well, he is a good student of the rules. He was told the regular rules about holding and hitting on the break. He didn't have any trouble with that."

Robert Byrd has been confirmed as the official in the ring for the mega-money fight this weekend by the Nevada State Athletic Commission.

Byrd has links to the UFC, as his wife Adalaide has worked as an MMA judge since 2006, notably officiating during both of McGregor's fights with Nate Diaz.

And, Cortez does not think his Hall of Fame colleague will have any trouble at all with McGregor's conduct during the most eagerly anticipated fight in recent memory.

"The referee will do an excellent job, he knows his job inside out, he's a Hall of Fame referee," Cortez stated.

"He has nothing to worry about with Conor."

Both McGregor and Mayweather have been working hard behind the scenes for Saturday's fight, even if they've been expressing differently in the public eye.

Mayweather has been seen partying and eating burgers, whilst Notorious has been as confident as always, claiming he'll knock Money out inside the opening rounds.

However, come Saturday, the talking stops, and the fighting begins.