Boxing: The bizarre rules for Mike Tyson comeback fight leaves UFC boss Dana White stunned

Dana White and Mike Tyson. Photo / Getty/AP

Mike Tyson, one of the most feared punchers in history, has apparently been barred from trying to knock Roy Jones jnr out in his comeback.

The 54-year-old Tyson faces multi-weight class legend Jones, aged 51, in Los Angeles on Sunday.

But the rules for the "exhibition" bout of eight two minute rounds have been released, and some are bizarre.

In particular, there will be no winner and no official judges – with celebrities used instead – for the contest between two boxing legends.

If either boxer suffers a significant cut, the fight is over. It is also reported they may also be banned from knocking each other out because of their age.

The fight is now being referred to in some quarters as "heavy sparring".

It has led to guffaws in a rival sport.

Mixed martial arts icon Dana White, head of the UFC, banged his head on a table in mirth when told of the rules for the bout.

"They're not allowed to knock each other out? How do you enforce that?" said White.

"I'd like to bet that doesn't happen. Can you bet on that? Oh s***, you can't even bet on this fight? I don't even know what to say to that."

"Iron" Mike Tyson was once known as the 'Baddest Man on the Planet', while Jones is one of the great pound-for-pound fighters.

It is 15 years since consecutive losses sent Tyson into retirement, while Jones left the ring two years ago on a winning note.

They won't wear headgear but will don heavier-than-usual 12 ounce gloves which will slow them down.

California State Athletic Commission executive officer Andy Foster said: "Technically there won't be a winner unless a knockout somehow occurs, or either fighter is deemed unfit to continue.

"They can move around and make some money, but I told them if you get cut, it's over."