By Laine Clark

At last, Alex Leapai gets a chance to exorcise the demons of his humbling loss to all-conquering world heavyweight boxing champion Wladimir Klitschko.

To do that he must silence cigar smoking, Dennis Rodman-lookalike Malik Scott in their bout in Logan, south of Brisbane, on Friday night.

Leapai's trainer Noel Thornberry has warned that his future career hinges on the result and he can't afford to taste defeat in front of his home crowd.

"How do you get another shot at the top level guys?" Thornberry told AAP.

"It is going to be very hard.

"Right now the fight with Malik is as important as Klitschko was at the time.

"That's the attitude we have going into this - it's the most important fight of Alex's life."

A calf complaint disrupted Leapai's preparation for the 10-round fight that may open doors to the lucrative US market.

However, Leapai (30 wins, five losses) was more troubled by the emotional pain of April's pummelling at the hands of Klitschko in Germany.

The dream of becoming the first Australian in 106 years to fight for the world heavyweight title became a nightmare as Klitschko picked Leapai off at will before a merciful end in the fifth round.

The usually quietly-spoken Leapai, 35, made it clear on Thursday how he intended to remedy that memory.

"I can't wait to get into the ring and rip his head off. For sure one of us is going to get knocked out tomorrow night," Leapai said.

And Thornberry is sure hoping Leapai is the last man standing.

A future fight with boxing's latest hot property Deontay Wilder in the US may await if Leapai wins.

And if he loses?

"It's important he wins otherwise it's another three or four years of very significant victories for him to get another chance (at a world title contender)," Thornberry said.

But he backed Leapai to finally shake off the shattering loss to Klitschko.

"For him there was definitely a low time after that fight," Thornberry said.

"This is super important to getting rid of those demons."

Scott was Klitschko's sparring partner for the Leapai fight - and the outspoken 33-year-old American promised a similar result.

The highly-regarded Scott (36-2-1) is also at the crossroads after losing two of his last three fights including a stunning first round knockout loss to Wilder.

He stood by his call that he would retire if he lost to Leapai.

"I mean it even more. I first said that when I was out of shape and now I am weighing something sexy so you can imagine how I feel now," he said.

"We are both coming off losses but this is my redemption."