In his pomp, Mike Tyson was one of the most fearsome and vicious fighters the planet has ever produced.

He ripped a mighty hole right through the middle of the heavyweight division in the 80's and early 90's to become the youngest heavyweight world champion in history.

Iron Mike was one of the first to truly prey on any mental frailties his opponents may bear using terrifying ring walks and brutal threats to unsettle his enemies before even throwing a punch.

Of course, once the punches started flying, there were few who could match his power and speed.

It seemed Mike was at the peak of his game, ready to take on all comers who might dare to irk him - he looked absolutely fearless. But was he truly afraid of nothing?

Well, according a memo that has emerged in The Sun, written by sports writer Fiaz Rafiq titled,' To The Top: Enter the Octagon, the Ring and Entertainment', even Mike had to draw the line at an offer he received in the 90's.

After Iron Mike was branded 'The Baddest Man on the Planet', a certain UFC champion took exception, challenging Mike to a winner-takes-all fight to crown the true greatest fighter in the world.

“[Tyson] was challenged by the Gracie Brothers, in particular Royce, back in the early 1990s.

“The UFC champion’s perception was that Tyson was the best boxer in the world, but he refused to accept that Tyson was the best ‘fighter’.

“The Gracies had a point. They had been beating all-comers from various styles long before the Octagon was first engineered.

“And Royce wasn’t going to rest until he did everything within his means to provoke the heavyweight champion into accepting a real fight in a no-holds-barred setting.

“To settle the matter once and for all, Royce formally challenged the most feared boxer of our time to a fight to the finish, and so did his elder brother Rickson.”

Unfortunately, Tyson declined the 'no-holds-barred' offer and the fight never happened.

His career then took a turn for the worse, spending time in prison before failing to reach the heady heights of his early career upon his comeback.

So, the Gracie 'fight to the death' fell into murk and obscurity.

All we can do is fantasise about the kind of spectacle it would have been but, if we look at it in the cold light of day, perhaps it is for the best that it never happened.