There are now just five days left ahead of one of the greatest fights in boxing history, between UFC champion Conor McGregor and a legend of the boxing sport, Floyd Mayweather.

Millions are expected to tune in for the clash at the T-Mobile Arena, which could become the most profitable pay-per-view event in the sport's history.

The fight has already been rife with contentious decisions and controversy, from debates over the size of the gloves to be used, to the refusal to allow Kenny Bayless the chance to referee, following disputable comments made by the 67-year-old last year.

The pre-event build up has been dominated by centrepiece press conferences between the two, noted for their infamous trash talking ahead of the clash.

And, although most of the exchanges constitute harmless trading of insults, the Nevada State Athletic Commission [NSAC] has stepped in to remind the entourages of the two stars over conduct in the lead-up to August 26.

Commission chief Bob Bennett warned the fighters over crossing any boundaries during the final few days of the build-up. 

He said: "It wouldn't be in [Mayweather and McGregor's] best interest to put their hands on each other, and they both know that.

"Both of them are professionals that know the repercussions from inappropriate behavior. I don't expect either one of them to get into any physical altercation. They are supreme athletes that know the rules and regulations."

Both Mayweather and McGregor have been involved in run-ins with the NSAC in recent years, with Mayweather questioned three years ago by the commission over the safety of his sparring sessions, ahead of facing Marcos Maidana.

McGregor paid a fine of $25,000 to the NSAC just earlier this year after water bottles were thrown during a press conference with counterpart Nate Diaz.

Despite the high-running of emotions as the fight nears, both fighters have remained disciplined thus far, with the NSAC and fans alike hoping that the two will save their aggression towards one another for when they step into the ring in under a weeks time.