Three-time world title challenger Matthew Macklin says he will retire if he loses to Jason Welborn when the two clash in Birmingham in October.
Birmingham-born Macklin, 33, is a former British and European Champion and is stepping down a division to light-middleweight for the fight.
"It's a step down for me but sometimes you have to regroup," said Macklin, who has lost six of his 38 contests.
"If I lost I'd definitely retire. I still want to be a world champion."
Macklin, who unsuccessfully fought for the world middleweight crown against Felix Sturm,Sergio Martinez and Gennady Golovkin, agreed to take on 29-year-old Welborn after the Black Country fighter's original opponent - Commonwealth champion Sam Eggington - was pitted against ex-world amateur champion Frankie Gavin.
|Matthew Macklin's world-class pedigree|
|Macklin's first shot at a world title came in June 2011 when he contentiously lost a split-decision to Germany's long-time champion Felix Sturm in Cologne.|
|He floored the great Argentine Sergio Martinez in his next title bout nine months later, but was eventually forced into an 11th-round retirement.|
|Macklin suffered a more comprehensive defeat when he was knocked out in the third round by current unbeaten champion Gennady Golovkin two years ago.|
"I can't afford to drop down to his level," Macklin told BBC WM 95.6. "I'm several levels above, I've consistently proved that.
"I'm conscious it's going to feel like a world title fight for him, so he's going to box out of his skin. He wants to get where I've been and I want to get back there - I have to train hard and do everything right."
Despite dropping down a weight level to meet Welborn, who has won 17 and lost three of his 20 contests, Macklin does not envisage that being an issue.
"They're probably hoping I struggle to make the weight but it's not going to be a problem," Macklin said. "I feel like going down to 154 pounds will give me a new lease of life."