MELBOURNE, Australia — Israel Adesanya defeated UFC middleweight champion Robert Whittaker with a stunning knockout in the second round of their highly anticipated 185-pound unification bout which headlined UFC 243 on Sunday.

New Zealand-based, Nigerian-born Adesanya landed a booming right hook which floored Whittaker in the final seconds of the first round and then ended the fight in the second of the five-round contest with a left hook.

Adesanya was interim champion before claiming the title against Whittaker and improved his UFC record to 7-0.

After doing a cartwheel during his entry to Docklands Stadium, Adesanya said he was determined to put on a show.

"I'm a dancer. I'm an entertainer, I have to give them a show and set the tone," Adesanya said. "There's no one like me. No one."

The 30-year-old said he had soaked up everything Whittaker could throw at him in the short bout.

"He caught me with a nice one, but I returned," Adesanya said. "I eat it, but give it back two times. I'm tough and smart."

The attendance of 57,127 set a world record for UFC, surpassing the 56,214 at the same venue in 2015.

"I was in the nose bleeds, and now I've made his nose bleed," Adesanya said immediately after the fight in reference to that 2015 event where he was a spectator in the upper reaches in the stadium while Whittaker was a rising UFC star on the card at that event. The New Zealand-born Australian Whittaker won his fight that night.

It was 28-year-old Whittaker's first fight since June 2018 in Chicago. He was scheduled to fight in February but withdrew due to emergency bowel surgery.

Whittaker's UFC world-title defence was the first by an Australian.

"He's a great striker and congratulations," Whittaker said. "I took the fight to him. It was tit for tat and I got caught. It happens.

"I'm 28. This is my first loss in the division. Trust me when I say I'm not going anywhere."

New Zealand's Dan Hooker scored a unanimous points win over higher-ranked American lightweight Al Iaquinta in the co-main event.

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