Primed Tszyu says he's twice the trainer his father was

Tim Tszyu has brushed off Tony Harrison's taunt that he's no Kostya Tszyu, warning the American he's twice the hard arse that his legendary father was.

As Harrison continues to question Tszyu's ability to step up a class for Sunday's world title fight in Sydney, the home-town favourite on Monday revealed he'd taken Kostya's commando-like training resume to extreme new levels in preparation for his date with destiny.

Tszyu (21-0, 15KO) is attempting to emulate Kostya in becoming world champion with victory over Harrison (29-3-1, 21KO) to claim the interim WBO super-welterweight belt at Qudos Bank Arena.

The undefeated 28-year-old says he's in the most supreme physical shape of his career after an intense five-week training camp.

"Everything has been on point," Tszyu said.

"I went and researched a little bit about Cristiano Ronaldo. I know he's not a boxer but the way he approaches life is the way I am approaching life right now - as a true, 100 per cent athlete dedicated to his craft.

"Everything. Just the way I eat, when I eat, just true professionalism.

"I know when I was growing up my dad was an army sergeant with the way he approached life and I'm times two to how he was."

The meticulous Tszyu, who even took a packed lunch to a promotional cruise around Sydney Harbour, says he feels invincible after completing two-and-a-half-hour sessions and wanting to go more.

"The funny thing is that as the rounds go up and up and up, I feel like I don't get tired. My breathing's on point and everything's just running smoothly," he said.

"Right now I feel like I could run over anyone and it's a good position and feeling to have, especially leading up to such a big fight."

The winner will take on undisputed champion Jermell Charlo later this year to unify the division.

Harrison is the only man to have beaten Charlo but is the bookmakers' underdog against Tszyu.

The 32-year understands why but plans on making a fortune backing himself.

"I've lost the last couple of times in the late rounds and he's the guy who's tough and strong, high pace," Harrison told AAP.

"So I definitely understand why they think that way or why they are setting this guy to win the fight.

"But every time they do shit like that, we kill 'em. We kill 'em.

"We've made like a year's monthly mortgage payments out of shit like that, me and the family.

"I always back myself. Always."