Australian UFC champ Robert Whittaker has been sensationally ruled out of his title fight at Rod Laver Arena, Melbourne on Sunday after a hernia issue has seen him rushed to hospital.

Whittaker, the middleweight champ, was supposed to be defending his title for the first time on Australian soil against American Kelvin Gastelum at UFC 234.

The Daily Telegraph understands the 28-year-old Sydneysider, who is undefeated in his past nine Octagon appearances, started complaining to his team of pain in his hotel room overnight.

The fighter dubbed Bobby Knuckles by fans was rushed to a Melbourne hospital this morning.

The result is a huge blow for the Australian who had sold out his first title defence on homesoil in just eight minutes.

Ironically, injury also forced Whittaker out of his last scheduled title defence in Australia, a UFC 221 clash with Luke Rockhold in Perth.

It is understood Whittaker started complaining to his coaching staff late on Saturday evening of pain in his abdomen.

A UFC spokesperson said the issue was not related to his weight cut.

As a result, the co-main between Brazilian great Anderson Silva and New Zealand phenom Israel Adesanya will now become the headline event.

UFC officials have said the fight will remain over three rounds, and not go to five - as is the case for headline events.

A lightweight clash between Lando Vannata and Marcos Rosa Mariano will now move to the main card.

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