As long as they turn up.

Hopoate said he was accustomed to being portrayed as the bad guy during his controversial league career and embraced that reputation as a boxer.

Headlining an all-heavyweight, five-fight card at Newcastle Entertainment Centre on December 4, Hopoate will fight fellow Sydneysider Michael Kirby for the vacant International Boxing Federation Australasian heavyweight title.

Promoter Nathan Swadling said the "heavyweight explosion" was the first program in Australia to consist of only heavyweight bouts.

Hopoate, who lost his Australian heavyweight belt when knocked out by Colin Wilson in New Zealand six weeks ago, said he was likely to retire if he lost to Kirby.

Wilson will defend his national title against Justin Whitehead on the undercard, which also features another league convert in Solomon Haumono plus Newcastle fighters Bobby Tuimaualuga and Daniel Ammann.

"If I lose this, that's pretty much it. It would be four losses and no one would take me seriously, so this is a must-win for me to see how far I can go in this sport," Hopoate said.

"When I played footy I hated losing. I did some dumb things on the football field but all of it was to try and win the game because I've got massive pride."

Hopoate was excited about fighting in "a good sporting town like Newcastle" but did not anticipate having too many fans in his corner.

"I think I'll still have the same boos as when I was playing for Manly. I don't think that's ever going to change. I'm John Hopoate; I'll be John Hopoate until I die," he said.

"People are still going to see me the way I was on the football field and that's life . . . At the end of the day, it doesn't matter if I'm the villain or not.

"Choc [Anthony Mundine] loves that . . . people hate him but they still pay to go watch him, and he makes a lot of money out of this sport."