Gallen branded Whittaker a "condescending prick" after preserving his undefeated record in professional boxing with a points decision over another UFC legend in Kiwi Mark Hunt in December.

Whittaker, though, maintains he respects Gallen's endeavours in the ring and that he'd happily take on Cronulla's only ever NRL premiership-winning captain if the right deal could be struck.

He reportedly wants $1.5 million.

"It's funny because a lot of people bring up Gallen and me potentially fighting him," Whittaker said after a sparring session with super welterweight world title boxing hopeful Tim Tszyu in Sydney on Tuesday.

"(But) I'm already in the fight game. It's not like I need to drag my feet to do it.

"If the money's right, I'll do it. If it's not, I'll just keep doing my day job, which is fighting.

"We couldn't get things organised fast enough before I took a fight with the UFC this time, so maybe opportunities will present themselves afterwards - but we'll have to wait and see."

Asked if he respected Gallen as a boxer, the the UFC's No.1-ranked middleweight said: "Certainly".

"I respect anyone that gets out there and works hard and does what they enjoy doing and dreams big," Whittaker said.

"I would never not respect hard work and effort."

In the meantime, Whittaker is focusing on his next UFC tussle with Brazilian Paulo Costa in Las Vegas on April 17.

Victory would earn the 30-year-old a world title fight.

"I thought I deserved one already, but one fight at a time," Whittaker said.

"If I do win, the world's my oyster."

Whittaker said cross-training with boxing ace Tszyu had him primed for Costa.

"I do believe iron sharpens iron," he said.

"So to get in there with his speed and his reactions and his presence in the ring, it's great to work my eyes and reaction speeds and muscle memory.

"He's so quick. So quick. He just fills the space so well."

Australian Associated Press