I meant to write this a month or so back, a year ago in fact. It's an ode to a single word, a symphony in ten letters.
Sport has true greats, colossae, but almost none can say this.
Arsenal 2003/4 managed it - Man U 99 won the treble, Chelsea 04/05 got more points, but Arsenal are remembered as invincibles.
Sugar-Ray Robinson was the man for who the "pound-for-pound" title was created - but it was Rocky Marciano who retired with a zero in the loss column.
And last night two such men collided, but the true great wasn't in the ring.
Mayweather is a study in classical boxing and dancing feet, deceptive power and determined defence. Hatton is warrior with astonishing power, energy and will.
But the true great was in the audience.
Joe Calzaghe has fought 44 professional fights and lost none of them. He has stopped his opponents inside the distance 32 times.
He is the first undisputed super-middleweight champion of the world, has held his WBO title for more than a decade and successfully defended his world title more than 20 times.
No one can say that. No one on the planet has held a world title that long. Only two men in the history of boxing have successfully defended their title more times - Joe Louis and the less well-known Dariusz Michalczewski.
To put this in perspective, Calzaghe won the WBO super-middleweight in 1997 - defeating Chris Eubank (himself undefeated at middleweight, winner of world titles at two weights and considered one of the greatest British boxers of the last 30 years). In 2005 Calzaghe - who despite holding a world title for eight years was still considered untested - came up against Jeff Lacey.
Lacey has rather dropped from the scene recently, but at the time he was mentioned in the same breath as Mike Tyson. He was undefeated, a world champion, and the pundits were predicting a drubbing for this no-name Brit. Calzaghe won every round, landing more than 1,000 punches in the process. It remains to be Lacey's only defeat.
After eight years of Being disrespected by the boxing community, Calzaghe's victory was so complete that he struggled to find an opponent in the wake of it.
But he did. And there was that pesky matter of the other word boxers love to have attached to their names - undisputed.
On November 4th this year Joe Calzaghe comprehensively defeated Mikkel Kessler to become the first undisputed supermiddleweight champion of the world.
Undefeated, undisputed, a world champion for more than a decade. And as I type this Sports Personality of the year.
If Floyd Mayweather really wants to be considered the best boxer, he should do what Hatton did - step up a weight class and test himself against another undefeated world champion. But he won't - because then there would be no doubt.
Joe Calzaghe is the greatest boxer currently fighting, and anyone who wants to disagree with me can step into the ring with him and lose.