Romero missed weight by 0.2lbs overnight - his second straight failed weight cut - removing the title from the equation.
No title fight for the main event but talks are ongoing about salvaging the fight.
"We came here to fight for the title", Romero said after the ceremonial weigh-ins, where he received a chorus of boos from the local crowd "I came here for the title fight".
The fight will still take place, and Whittaker will retain his title if he wins.
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The U.S. troops were there to provide advice, assistance and aerial surveillance, the statement explained. Al-Shabab has been blamed for the October truck bombing in Mogadishu that killed more than 500 people.
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It is now the 10-leading cause of death in the USA , and is one of only three leading causes of death that are on the rise. Cultural attitudes may play a part . "We have to keep working on stigma", Zietlow-DeJesus said.
Welbeck: United's Rashford benefiting from free role with England
However, it was another youngster in Rashford, 20, who caught the eye from the off. By taking risks they show the glimpses of quality like Marcus's opening goal.
He didn't have enough for Mike Jackson (1-1 MMA, 1-1 UFC), though, who earned a unanimous decision victory over Punk and likely ended the UFC tenure of the former pro wrestling standout. It's not only a fight for a fight - I want to fight for the title.
Given that he was competing for the UFC belt, he had to make "championship weight" of 185lbs or under. It would make me upset if my opponent missed weight because I believe making weight is half the job; if you don't make 84.5 [kilos, 186lbs] then we're not in the same weight division.
In what was supposed to be his first title defence, Australia's first UFC champion will face the man he fought and beat in his last outing.
The hugely divisive Colby Covington takes on Brazilian Rafael dos Anjos having called Brazilians "filthy animals" and CM Punk of WWE fame steps into the octagon for the second time.
Camera IconCan Robert Whittaker overcome Yoel Romero? "I don't know what they're going to do".