Okamoto reported Saturday that Whittaker was taken to the hospital after he felt pain in his abdomen Friday night:
Per Okamoto, White also revealed Whittaker will undergo a procedure Saturday to address the issue. The hospitalization was not the product of any weight-cutting attempts.
Gastelum later took to social media to confirm the fight is off:
Whittaker (21-4-0) is the middleweight champion and was looking to defend his title against Gastelum (16-3-0). He last fought June 9, 2018, when he defeated Yoel Romero via split decision.
In July 2018, Whittaker told Ariel Helwani (h/t ESPN's Greg Rosenstein) that he would not be able to defend his title until 2019 because of injuries. He broke his right hand against Romero and suffered ligament damage in his left hand. He underwent surgery and used the second half of the year to recover.
The 28-year-old has not lost a fight since 2014, when he was bested by Stephen Thompson. His unbeaten streak spans his last nine bouts.
Here is a look at the updated UFC 234 card, with the Israel Adesanya-Anderson Silva clash now headlining the event:
Whittaker's withdrawal takes away some star power, but there is still plenty to keep an eye on throughout the night.