In a later statement, UFC said Whittaker had undergone emergency surgery due to a "severe abdominal injury".
Anderson Silva against Israel Adesanya has been moved up to the main event.
Adesanya vs Silva will be the co-main event of UFC 234, with Middleweight champion Robert Whittaker putting his title on the line against Kelvin Gastelum in the main event.
UFC president Dana White told ESPN that Whittaker had been taken to hospital after complaining of stomach pain and was diagnosed with a hernia.
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The market experienced a slowdown in inflation which fell to an 18-month low of 2.19 percent last December, the report added. Mr Carney said: "When the economy is growing more slowly, the probability of it having a negative quarter or two goes up".
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Some experts also see a risk that Chinese intelligence may develop an ability to subvert Huawei's equipment. It is a complicated process and will take at least three to five years to see tangible results.
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NewPort Goalkeeper Joe Day cut short his team's celebrations to race to his wife's side as she gave birth during the match. Day had just kept a clean sheet as Newport won the FA Cup fourth round replay 2-0.
For all the good luck that the UFC had in keeping fights scheduled through January, February is not starting off the same way.
ESPN's Ariel Helwani does not paint a pretty picture of what occurred that night, with Whittaker now in surgery.
Silva, 43, broke into tears during the UFC 234 official weigh-in. The bout will determine the next contender to the title, likely after Whittaker defends vs. Gastelum.
It marks the second time Whittaker has been forced to withdraw from a scheduled title fight in Australia. The Brazilian will take on a fighter 14 years his junior in Adesanya, who is sixth in the UFC middleweight rankings and 15-0 in his MMA career. We still will be getting what should be a stellar middleweight showcase in the main event with a prominent name attached - it just won't be contested for the 185-pound title.