Bitterly disappointed in being forced out of the main-event in front of his home crowd, Whittaker addressed his fans on social media and revealed his "potentially fatal" injury.
Whittaker said: “Let me say that I’m sorry to all my friends and family and fans that came out to watch me perform. But unfortunately I couldn’t be there. I tried my best to try and swing it.
“I was fighting the doctors all the way up until they said, ‘You’ve gotta get surgery or you’re gonna lose part of your bowel.’ Or it could be potentially fatal. I had to look at my health first — I’m sorry, guys.
“You guys know what it takes to keep me from the octagon. So for you guys to be behind me and supporting me and sending me your love like that, it means a lot to me. It really does.
“And it makes it easier for me to try even harder next time, to get in there and to put my soul on bare and put on a good show for you guys.”
After UFC 234, Dana White revealed Whittaker had pleaded to fight on - but the severity of his injury was far too devastating.
Gastelum, though, claims he is rightfully the UFC middleweight champion and paraded around the arena with Henry Cejudo’s flyweight title.
The stunt was seen as a way of making sure Gastelum is not overlooked for the next crack at the title - while some accused the 27-year-old of just being delusional.
One person not impressed with the Amercian’s actions is former two-weight UFC champion Conor McGregor - who blasted “worm” Gastelum.
McGregor said: Why is that worm holding the 185lb belt? There are worms crawling on his skin!
“It was absolutely ludicrous to even consider allowing him to compete. Let alone now walk around the arena shaking our fans hands.
"Someone sort this, this instant. And sterilize that belt.
“Immediately.”
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