Simply beating Paulo Costa won't satisfy former UFC middleweight champion Robert Whittaker.

Acknowledging what's at stake, the Australian wants to "finish him" and show he still belongs among the combat sport's big fish.

Whittaker (25-7) is desperate for another crack at the middleweight title after two losses to Israel Adesanya and a shock defeat to new champion Dricus du Plessis in July last year.

The 33-year-old hasn't registered a knockout since 2017 and has attacked his preparation since the du Plessis loss with that drought in mind.

"Every time I hit a session I was trying for it to be the best session I've ever done," he said ahead of Sunday's (AEDT) UFC 298 in Anaheim, California.

"It's nothing personal ... it's the fight game. I don't want to just win. I want to get in there and finish him.

"That is how I will get satisfaction."

Brazil's Costa (14-7) hasn't stepped into the octagon since beating Luke Rockhold in August 2022, injury and managerial dramas slowing his progress.

"I'm expecting the best version of him," Whittaker said.

"That's the safest approach ... I'm covering my bases you know, I'm coming in there ready for the war."

Fellow Australian Alexander Volkanovski will headline the card, defending his featherweight title for a sixth time against undefeated rising star Illia Topuria.

"He's (Topuria) a nightmare in the division, but it's very hard to bet against Volk," Whittaker said.