When Miguel Cotto steps into the ring in Madison Square Garden on Dec. 1, he will be challenging not just Austin Trout for his WBA super welterweight title, he will be facing Father Time as well.
And while Cotto is not old—he just recently turned 32—he's at that tricky age for a fighter where things can go south overnight.
You get into the ring and you're a half-step slower, or your punches hit with slightly less thud than before or you can no longer fight three minutes of every round.
This risk is amplified for Cotto by the fact that the man standing in front of him, Austin Trout, is a young, hungry champion with something to prove.
Now, people will rightly point to the last time we saw the Puerto Rican sensation in the ring, a spirited but decisive loss to universally recognized king of the sport, Floyd Mayweather, Jr., as proof he still has much left.
What remains to be seen is if that was a resurgence or a last hurrah.
This is not to say that Miguel Cotto will fall victim to this phenomenon; just that we should take the stories of the following five men as a cautionary tale.
Pacquiao ran over De La Hoya like a buzzsaw.
"The Golden Boy" was more than just a boxing star, he was a mainstream celebrity and all his fights were sports events.
By 2006, Oscar De La Hoya had begun to wind down his career, but proved he still had something left when he dominated, and knocked out, the Nicaraguan madman Ricardo Mayorga. It was the culmination of a highly personal feud between the two and paved the way for a superfight with Floyd Mayweather, Jr.
The bout in 2007 showed De La Hoya still had something left, as he gave Mayweather all he could handle in the first half of the fight. At the midway point, many felt Floyd could be on his way to his first defeat, but he rallied to win the later rounds and a split decision.
De La Hoya would next host a sort of farewell fight, not on pay-per-view for the first time in years, dominating former world champion Steve Forbes.
This set up a match with rising sensation, and future Mayweather rival, Manny Pacquiao.
The fight, which was held at welterweight, was highly anticipated, and many observers felt De La Hoya's size and experience would win the day.
They couldn't have been any more wrong.
Pacquiao absolutely dominated De La Hoya, not just winning, but beating him up in a way nobody ever had in the past.
Oscar was lethargic, seemed to never find his rhythm and looked weak in the legs. It was the most dominant defeat he suffered in his entire professional career.
He would retire shortly thereafter.
Norris dominated Leonard.
Sugar Ray Leonard is one of the greatest boxers in history. Period.
But like many others, he made the mistake of hanging on for one, or in his case, two too many fights.
Leonard's second comeback began well. In an odd circumstance, he defeated Don LaLonde for the WBC light heavyweight belt and also won the newly-created WBC super middleweight title.
The fight, which took place at 168 pounds, netted Leonard two championships in two different weight divisions.
After a draw with Tommy Hearns and a rubber match victory over Roberto Duran, Leonard dropped down two weight classes, from 168 to 154 pounds, to challenge for a junior middleweight title.
His opponent was WBC champion "Terrible" Terry Norris, a nickname he lived up to, making Leonard's night a living hell.
Norris dropped Leonard twice and dominated him, winning a lopsided unanimous decision. The man who, in his previous fight, had beaten Roberto Duran had gotten old overnight, and a younger champion made him pay.
In January 2009, Shane Mosley turned in one of his career best performances—battering and beating Antonio Margarito in epic, one-sided fashion.
It was a stunning result, as Margarito had never before been stopped and was coming off a career-defining win over Miguel Cotto.
But Mosley turned in a total beatdown of the Tijuana Tornado, knocking him out in the eighth round. It would turn out to be his last victory.
It, and his mouth, propelled him into a showdown with Floyd Mayweather in which the then 39-year-old Mosley looked shot. He had a good second round where he stunned Mayweather, but seemed every bit his age from that point forward.
You can give credit to Mayweather for shutting him down, but this argument loses points when you consider Mosley struggled to a draw against Sergio Mora, who wouldn't last four rounds with Shane in his prime, in his next fight.
Shane Mosley aged seemingly overnight after putting forth a stellar show in his last win.
Few fighters had the overall skill-set of Roy Jones Jr.
There was a time when Roy Jones, Jr. was the undisputed king of boxing. He had speed, power and defensive abilities that few in the sport have ever shown in the ring.
His reign at light heavyweight was legendary. He held literally every major sanctioning body championship, and seemingly even a few that were made up specifically for him.
It was a spectacle just watching Roy walk to the ring with 20 guys carrying all the hardware.
Bored with the lack of challenges at 175 pounds, Jones elected to jump two weight classes to try and become the first fighter who began his career below middleweight to win a heavyweight title. And he did just that, easily defeating John Ruiz, one of the worst heavyweight champion's in history.
It would prove to be Jones' last dominant performance.
He would move down to face the man who would emerge to become his chief challenger at 175, Antonio Tarver, and while he won, it was clear the Jones of old was a thing of the past.
This was confirmed in the rematch when he was starched by a tremendous Tarver left hand in the second round, ending his night and his reign.
It would become a pattern for Jones in the twilight of his career. He would also get knocked out by Danny Green and Denis Lebedev, two men who Jones would've boxed circles around in his prime.
Tszyu is a Hall of Famer.
Many people seem to forget how good Kostya Tszyu was in his prime. He is a former four-time junior welterweight champion, a former undisputed junior welterweight champion and the first man to unify the division in decades.
Coming into his 2005 fight against rising British star Ricky Hatton, Tszyu had not lost a fight in nearly eight years and had held The Ring Magazine 140-pound title for nearly four years.
Tszyu started off the fight slowly against Hatton, as was his trademark of taking a few rounds to get going. He rallied in the middle rounds, but tired quickly as the fight went along.
Hatton's inside fighting, and many would say rough tactics, began to take their toll on the then 35-year-old champion. He would refused to come out of the corner for the 11th round, ending the fight and his career.