Former adversaries Shane Mosley and Ronald 'Winky' Wright have both announced their retirement this week.
Their colourful careers crossed in 2004 when Wright shocked Mosley - hot off a second victory over Oscar de la Hoya - to become the undisputed light-middleweight champion.
Wright also won the rematch later that year but was largely avoided thereafter due to his difficult southpaw style, and he never defended the titles.
He later stepped up to challenge middleweight champion Jermain Taylor, earning a draw, but fought only four times after that losing on three occasions.
His comeback at the weekend at the age of 40 did not go to plan, losing to the unbeaten Peter Quillin on points.
"Part of being a boxer is knowing when to call it quits," said Wright. "It's time for me. I did what I set out to do and that was to be great and become a world champion.
"I have a lot of great memories from my career and will still support this great sport which I have dedicated my life to. I want to thank all of the people who helped me along the way and especially the fans that supported me all of these years."
Mosley, however, went on to fight nothing but the best despite those losses to Wright, becoming a four-time champion in three weight divisions.
But he was past his prime when losing landslide verdicts to Floyd Mayweather and Manny Pacquiao in recent times, and has finally called it a day - also aged 40 - after one final payday against Saul Alvarez, to whom he lost last month in another one-sided contest.
'Sugar' Shane was virtually unbeatable in the early days, capturing the IBF lightweight crown and finishing that part of his career with a 31-0 record.
Mosley moved up to the welterweight division to pursue bigger paydays, however had he stayed at lightweight he would surely have shined for many more years before he eventually suffered his first loss.