Cain Velasquez is out of his heavyweight title clash with Fabricio Werdum at UFC 180, with Mark Hunt stepping up a replacement to fight the Brazilian will now fight Werdum for an interim title.
Velasquez suffered a knee injury during training and it means that the current UFC champ has to withdraw, and see either Hunt or Werdum crowned as temporary champion in his place.
With the change to the main event, the UFC have announced that they will be refunding tickets for the event.
The event sold out in super-quick time once tickets had gone on sale but it's unclear now just how much the UFC may struggle to fill the arena, or bring fans in.
How many refunds will there be?
Velasquez had been lined up for the UFC's long anticipated Mexico debut for a while, with the hopes that he could spark a 'golden age' of MMA stars from the boxing mad country.
"I’m sorry to the fans in Mexico who were expecting this fight, and I hope to be able to come down and still be a part of this historic event.” He told UFC.com.
Instead, those fans will have to watch as either a Brazilian or New Zealander/Australian walks out as the new Interim champion.
Super Samoan's comeback story nearly complete
For Hunt, this is his chance to cap off perhaps one of the most sensational comeback stories in modern sport.
The 40 year old, who originates from New Zealand but identifies himself as Australian, didn't win a single fight between July 2006 and February 2011, going 0-6, while facing the likes of the great Fedor Emelianenko and current UFC stars Alistair Overeem and Gegard Mousasi.
It was on the preliminary card of UFC 127 that Hunt set about changing his career.
That night in Sydney, he beat Chris Tuchscherer via KO and since then he's 4-1-1, with his only loss being to Junior dos Santos and going the distance to a draw with Antonio Silva - who later failed a drugs test.
That comeback started with a brutal walk away KO of Tuchscherer and it's only fitting that his rise to the top was capped off with another walk away KO of Roy Nelson.
Back in the Hunt for top prizes
It's the kind of comeback that seems more fitting of a Hollywood writer's room than the UFC octagon but it's happened and come November 15th, Hunt has the chance to become the UFC Interim Heavyweight champion.
While it may only until Velasquez returns, it will still be everything that nobody expected from Hunt back in 2011 and his thoughts on the shot?
“I feel blessed to have this opportunity to fight for another world title. This is something that doesn’t happen often to people. First K1 and now UFC – how can I say no, even though it’s on short notice? I’m dropping everything and flying to Mexico tomorrow so I can best prepare myself for this fight. I have to get into shape and acclimatize to that environment, which is really important.
“There’s nothing to lose when you’re competing against the best at the top level,” Hunt added.