Jack Brubaker has questioned Tim Tszyu's passion for boxing ahead of their blockbuster bout in Sydney on Friday night.
It will be a St George-Sutherland Shire derby at the International Convention Centre when Cronulla boxer Brubaker takes on Rockdale fighter Tszyu.
Brubaker will step up to super welterweight to take the bout against Tszyu, widely regarded as the next big thing in Australian boxing.
The 28-year-old Brubaker, who enjoys a 16-2-2 record, is considered an underdog to hand Tszyu his first professional defeat.
But while Tszyu will have his legendary father, Kostya, in his corner, Brubaker will have a legend of his own having worked with multiple world champion Jeff Fenech in preparation for the bout.
Brubaker has seen rapid improvement throughout his training camp and is confident of causing an upset, questioning Tszyu's desire and saying the 25-year-old was under immense pressure.
"If it wasn't for Tim's last name he'd be fighting at Punchbowl Workers Club," Brubaker told the Leader.
"But the Tszyu name means he's got people behind him, the sponsors. I don't feel the love for the sport is there for him.
"I got face to face with him [at a media day last Wednesday] and it was a good chance to have a look at him.
"I just don't see it in his eyes. He says 'it's a serious business, it's not fun.' Mate, if you're not enjoying your career go do something else. You don't have to waste your life trying to fill your dad's shoes.
"He's got the weight of the world on his shoulders. So many expectations. A fight against me is dangerous. He's got a lot to lose. Me I'm the underdog, I've got nothing to lose and everything to gain which makes me so dangerous.
"The pressure is on him. I reckon Tim is one of those people that if he were to lose to me he'd never come back to the sport. He had a successful amateur career and went missing out of the sport for three or four years. He's got that in him.
"He's got a rematch clause that he hasn't signed with anyone else, which I hope he does take up because it's worth good money for me and I'd love to beat him twice. But Tim is one of those people, I can see him go missing from the sport.
"We signed a rematch clause for when I beat him. He put it in the contract. It hasn't been in [the contract of] any of his last few opponents. He wouldn't put it in there if there isn't the possibility of me winning and he's obviously thinking about it."
Brubaker acknowledged it was the biggest fight - and biggest opportunity - of his career. And while he has achieved plenty so far, a headline win in a pay-per-view fight against the golden boy of Australian boxing would top everything.
"[A win] means everything. I've given up a lot, made a lot of sacrifices," he said.
"I've lost a lot of close friends because of boxing. It's a selfish sport and you need to be selfish to succeed. I have a lot of support from my family but it has been tough. There's nothing easy about it.
"I've always had to do it the tough way. I haven't been babied. I've always taken the toughest fights. I've traveled, fought the best in Japan, been on the undercard for Danny Green. But I'm always the underdog and no one has really backed me. But when I win this fight I will be where I deserve to be.
"Right now with Tim and his last name the whole of Australia is behind him. The bandwagon boxing fans who have probably never watched any of his fights are behind him. I've copped a bit of flack from the boxing community but I thrive on that. I love proving people wrong. I'm a big underdog and that excites me. And everyone can come back to me and eat their words and say they were wrong.
"Day by day I'm getting more and more confident. I wouldn't have taken the fight if I didn't think I could beat Tim. I knew 10 weeks ago it would be a tough fight. But this last week in particular I can just smell something in the air. You can feel it. This is what I'm destined for. These big fights on the biggest cards, the big stage. I thrive on it.
"My body feels better than it ever has. Seeing him and his attitude and mentality makes me even more confident. I go to sleep and wake up more confident. By the time I get in the ring I'll be jumping out of my skin."