Whittaker out of fight vs. Gastelum at UFC 234

Robert Whittaker reacts after his middleweight mixed martial arts title bout against Yoel Romero at UFC 225. (Jim Young/AP)

MELBOURNE, Australia — Australia’s UFC middleweight champion Robert Whittaker withdrew from his championship defence against Kelvin Gastelum on Sunday at UFC 234 because of an abdominal injury and subsequent emergency surgery.

UFC president Dana White says the 29-year-old Whittaker, who has a record of 20-4, became ill Saturday night and complained of pain in his abdomen before being diagnosed at a hospital with a hernia.

In a later statement, UFC said Whittaker had undergone emergency surgery due to a "severe abdominal injury."

The highly anticipated No. 1 contender match between rising New Zealand star Israel Adesanya (15-0) and Brazilian veteran Anderson Silva (34-8) will now serve as the main event on the Rod Laver Arena card.

Also elevated on the card was the lightweight bout between American Lando Vannata and Brazilian Marcos Mariano.

Whittaker’s manager Titus Day said Whittaker first reported some issues around 6 p.m. on Saturday.

"Rob said he was a bit bloated and a little bit tired which is not uncommon when you are going through the process they are going through, reloading and putting some food back in your body," Day told Australian Associated Press.

"Then about 10 o’clock we got a call from (Whittaker’s wife) Sofia saying he’s got some bad stomach cramps and he’s in quite a lot of pain and can’t sleep … it got to the stage at about three in the morning where he was taken to hospital."

Gastelum tweeted with "much sorrow" that the fight was off.

"I wish ↕robwhittakermma a speedy recovery champ! Get well soon!"

Tickets for the 15,000-seat arena sold out in eight minutes. UFC has offered full refunds due to the cancellation of the main bout.

It marks the second time Whittaker has been forced to withdraw from a scheduled title fight in Australia. Injuries kept him from fighting Luke Rockhold at UFC 221 in Perth last year.

Earlier this week, White had said the winners of the Whittaker-Gastelum and Adesanya-Silva fights would meet later this year.

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