MIAMI, Florida (CMC) — Veteran Jamaican light heavyweight boxer Glen Johnson is prepared to unleash everything he has when he tackles American Yusaf Mack in a world title eliminator tonight.

At 41 years old and coming off two losses in his last four fights, former world champion Johnson must win to keep his career alive and promised no mercy for the 30-year-old Mack in their rescheduled International Boxing Federation (IBF) world title eliminator.

“This is a fight that I have to have and there will be no mercy for Mack on my behalf come Friday night,” Johnson said.

The bout was originally slated as the co-main event for the cancelled January 30 Andre Berto-Shane Mosley card in Las Vegas and will now be staged at the NSU Arena in Fort Lauderdale, Florida.

Miami-based Johnson is in his home state and declared himself satisfied with his readiness for the high-stakes bout.

“I completed training camp and I’m good to go,” he said.

The 12-round clash, to be televised by ESPN2, will provide the winner with an automatic world title path as he will be the IBF’s mandatory challenger to fight champion Tavoris Cloud, probably in May.

Mack has also spoken confidently going into the fight he describes as the biggest of his life.

“I am in the best shape of my life, I have worked really hard and cut no corners and I am ready to light up the light heavyweight division,” said Mack, who is on a five-fight winning streak.

The ageing Johnson carries a record of 49 wins (33 knockouts) against 13 losses and two draws, while Mack has 28 wins (17 knockouts) against two losses and two draws.

Johnson’s two losses in the past two years — both to American Chad Dawson — appeared to sink his career but he has not given up on his dream to reclaim a world 175-pound title.

He has been among the most prominent light heavyweights in the world this past decade — a three-time world title challenger before winning the IBF championship in February 2004 when he landed a 12-round unanimous decision over Britain’s Clinton Woods.