And then, from hour to hour, we rot and rot.

This emotive quote from Shakespeare’s As You Like It highlights the constant and somewhat depressingly inevitable march of human life from vitality towards decay. A quote that symbolises the fleeting nature of our very existence and death's inevitability. Happy Monday by the way.

I thought of The Bard and said quote immediately after reading that Floyd Mayweather is launching a boxing comeback at the venerable age of 49. It’s out there officially now that, on April 25, Mayweather and Mike Tyson will headline an event in the Democratic Republic of Congo. Following his exhibition bout with Iron Mike, Mayweather will resume his professional career with a September 19 fight against Manny Pacquiao.

Mayweather vs. Pacquiao. Two names who have transcended the sport. Two bona fide boxing legends. It’s huge news. The problem is it’s not 2009. You see their first fight - which didn’t deliver as a contest - happened five or six years too late. And that was 11 years ago.

From 2009 to 2014, all I seemed to read about was Floyd and Manny not fighting one another. Then on May 2, 2015, at the MGM Grand Garden Arena in Las Vegas they did fight, and it was billed as ‘The Fight of the Century’.

Underwhelming doesn’t quite cut it. It became the highest-grossing boxing match in history - generating over $600 million in revenue - but Mayweather cruised to a safety-first wide and uneventful decision win. In terms of their rivalry being put to bed that, we thought, was that.

Mayweather has been retired since knocking out UFC legend Conor McGregor in the 10th round of a one-sided super fight - the second-highest grossing fight of all time - in August 2017.

The shameless cash grab against Tyson in April is not surprising at all. They will move around and both men will presumably be well rewarded financially. However, I am surprised that he plans to have another sanctioned professional fight against Pacquiao, putting his fabled legacy and legendary ‘0’ status on the line in a real fight.

What motivates an undefeated 50-0 boxing legend to return to the sport as he approaches quinquagenarian status?

There was a time when the lights rose for him. Not just the arena lights. The whole world seemed to lean forward when Floyd sauntered to the ring. He was the champion. The Nonpareil. Untouchable in the squared circle. Green and gold around his waist, silk on his shoulders, excitable cameras chasing him through hotel lobbies in Vegas like he was the last honest myth left in sport.

So why is he coming back? Why now?

Mayweather built a brand on one word: Money. Rumours abound that this return to the prize ring is happening due to Floyd not having the cash he once did. But they remain just rumours. Only Mayweather and his bank manager will know the absolute truth.

There is nothing new under the sun of course, and tales of boxing legends being forced to return to pay bills are nothing new.

It doesn’t happen all at once. Money doesn’t disappear with a bang. It leaks. Lifestyle creep, also known as lifestyle inflation, is the phenomenon where your expenses rise alongside your income, causing former luxuries to become perceived necessities.

And isn’t there something undeniably human about a champion who spends like a sailor, falls, gets up, and tries again - even if the motivation is less “destiny” and more “overdraft” at this point?

The motivation may not be purely financial of course. We have been here before. This will actually be Floyd's fourth comeback from retirement, having previously retired in 2007, 2015 and most recently in 2017 after the McGregor heist.

Does a person really have to be broke to make money doing what they've excelled in all their life? He’s the self-styled best ever to do it.

Rich people who don't necessarily need the money don't stop making money. Privately he probably thinks he is still the best fighter in the world. Mayweather's ego is central to his persona, branding, and immense success, characterised by extreme self-belief.

Haters may point to that fact that he announces a return after Terence Crawford announces his retirement from boxing as being more than just coincidence. Again, that’s mere speculation.

The comeback is fascinating whatever way you look at it. Fascinating. And while we can speculate about the motivation behind the decision, what is not open to debate is the fact he is just not going to be the same fighter that we watched slack-jawed in awe during his peerless peak.

At least Floyd is not egotistical enough to come back and risk his boxing bequest against a current world champion. Pacquiao himself is 46 and several years remove from his own remarkable zenith. But there is jeopardy in this fight. The 68-8-3 (39) Filipino looked decent in fighting Mario Barrios to a draw for the WBC welterweight title last summer.

Floyd is not coming back and lining up a couple of fighters that old timers such as Bert Sugar or Cus D’Amato might refer to as ‘chopped liver’. Pacquiao gets another chance to destroy Mayweather’s perfect pro log, and that should be motivation enough.

The early betting lines for this have Mayweather as a 4/7 favourite, so while he is favoured with the odds compilers, they certainly do not consider him banker material.

• Read next | When could Moses Itauma win a heavyweight world title?

This fight may be a pure nostalgia hit, but it is also intriguing. I mean can you even put a cash value on your own sporting legacy and that mythical ‘0’? Clearly, the American can.

Mayweather believed in two things: hard training and harder spending. And he could spend it alright. Put it this way, his accountant must have had a sense of humour and probably believed in prayer.

Mayweather said he has "nothing left to prove in boxing" after beating Andre Berto to equal the legendary 49-0 benchmark set by former heavyweight champion Rocky Marciano. That was back in 2015. The truth is a lot of champions think the money will last longer than the applause. For most, it doesn’t.

Father Time will always be undefeated in sports, but Mayweather came about as close as any fighter can come to beating him, which makes his decision to come back even more intriguing.

Know this. ‘One last dance’ often ends in a stumble and ultimately, for every George Foreman who successfully recaptures all the gold in his 40s, there are dozens and dozens of other great champions who risk becoming a cautionary tale as they simply didn't know when to say enough was enough.

And so, from hour to hour, we ripe and ripe,

And then, from hour to hour, we rot and rot.

Sign up to DAZN Ultimate Tier to get PPVs included in your subscription 

Subscribe to DAZN's new Ultimate Tier to get a minimum of 12 PPV events included per year, including Derek Chisora vs. Deontay Wilder (April 4), and Wardley vs. Dubois (May 9), on top of another 185 fight nights. Plus Serie A football, watch on multiple devices, and many more extra benefits.

Sign up for £22.99 in the UK / $44.99 in the U.S. More details here.