Derek Chisora has offered a brutally honest reason for why he will retire after fighting Deontay Wilder.
Chisora (36-13, 23 KOs), now aged 42, will enter the ring for the 50th time on April 4 in London to face Wilder (44-4-1, 43 KOs).
He then intends to step away -- and not make a U-turn with his decision -- because of the increasing physical difficulty in preparing for a heavyweight fight.
"I am not coming back," he told Queensberry. "I will tell you why. Because I don't have any more training camps in me. That is God's honest truth.
"It happened at the Otto Wallin fight. The training camps became harder.
"I got in the ice bath in the morning, I go in the evening, so I can sort my body out."
A year ago, a bloodied Chisora valiantly defeated the younger Wallin but his career, which has made him a cult hero in Britain, is now weeks away from concluding.
However, he understands why boxers notoriously struggle to say goodbye to the ring.
"You don't leave boxing. It's a life. Nobody leaves boxing. Even at your grave, there will be boxing gloves on your tombstone," he said.
"It's in the blood. Muhammad Ali has been gone for a while but his daughter laced up the gloves, his grandson laced up the gloves. Do you understand?
"You can never retire from boxing. When one person in the family arrives in boxing, they all do.
"How many times has Tyson Fury retired? 'I am quitting, I am not coming back!' Liar! We know he never left, he was just trying to tell himself that he retired."
Fearsome former WBC champion Wilder and Chisora have enjoyed a cordial relationship in the build-up to their fight so far, even negotiating the terms privately via FaceTime.
It is a far cry from the Chisora who brawled with David Haye in a news conference, and overturned tables opposite Dillian Whyte.
"When you get to 40, there is nothing else to prove," Chisora explained.
"Now, you have a lovely meal softly and quietly, you drink chardonnay and wine. In your 40s you drink good wine. In your 20s and 30s you drink sambuca!
"In your 40s you don't drink sambuca because you know it will take months to recover!
"The way we want to sell this fight? I don't want to bring something out which isn't there.
"I can guarantee [in the fight] it won't be friendly."
Chisora is not concerned about being humiliated by losing his final fight in front of a home city crowd.
"There is never embarrassment in life. This is the problem we have in life -- 'if I do this, I could be embarrassed,'" he said.
"But there is no embarrassment, it's just life. If I get knocked out, then I get knocked out. That's life."