UFC hosted their annual pay-per-view live from Australia this past weekend, and whilst not being the strongest card overall that they've ever held, two Middleweight fights held top billing with huge importance.

The upstart Israel Adesanya took on the legendary figure of Anderson Silva, whilst the champion Robert Whittaker returned to his homeland to face Kelvin Gastelum.

At least that was the plan, but things took a turn for the worse just seven hours before the start of the main card.

Whittaker was reported out of the fight due to a serious injury, and the whole co-main was scrapped with no replacement.

It was revealed that Whittaker had suffered a hernia, but no-one knew how serious the condition was until the Aussie revealed all on his Instagram earlier today.

"I'm still in the hospital, I had to get emergency surgery on Sunday because I had a collapsed bowel and an internal hernia that was causing me all sorts of problems," stated Whittaker.

"I'm sorry to all my friends and family and fans who came out to watch me perform but unfortunately I couldn't be there.

"I tried my best to swing it and I was fighting the doctors the whole way up until they said 'you have to get surgery or you'll lose part of your bowel or it could be potentially fatal' so I had to look at my health first.

"It is what it is, you can't plan for these things. I'm sorry to Gastelum because he came out here, prepped and I couldn't give him a show.

"You guys know what it takes to keep me from the Octagon so for you guys to be behind me like that it means a lot to me.

"It makes me easier to get in there and try harder next time and put on a good show for you guys."

Whittaker also thanked his team-mates, Dana White and the UFC medical staff for helping him out as he starts the road to recovery.

You can watch the full video below.

It's a scary thought that the situation was potentially life-threatening, but it looks like Whittaker will be on the road to recovery in the near future.

That leaves the middleweight division in a bit of a predicament though, with the champion sidelined once again.

Gastelum paraded himself as the 'new champion' at the event, but many fighters said it was embarrassing, including Adesayna, who after his victory over Silva told Gastelum to put the belt down.

We could eventually see an interim bout between the two as we wait for Whittaker to make a full recovery - and how exciting would that be?