From the rookie debutant to the nation's leader, Rory reaches his centenary
Sometimes it seems as if leaders simply emerge from the shadows until you realise that they were there all along.
How does one possibly follow in the footsteps of not only the greatest Irish player ever but also its most inspirational?
By leading the country to the uncharted waters where, for all their gifts, Brian O'Driscoll and Paul O'Connell had never once discovered during over a decade of their respective captaincies.
Eleven years ago, Simon Easterby was a grizzled pack veteran and captain of a side missing their twin talismans, and enduring familiar, humbling defeat to a weakened All Blacks; 45-7.
When Best trundled on to make his debut against in the front-row - alongside brother, Simon, as it happened - one wonders whether his back-row colleague would have contemplated the then pudgy farmer winning his 100th cap, as Ireland captain, all these years later.
And a captain who, unlike his vaunted professional predecessors, from Wood through to O'Driscoll though O'Connell, boldly broke new ground with Ireland, from beating South Africa on their own soil to engineering another historic breakthrough by removing a 111-year black-clad monkey.
Today, Ireland could become only the third team in history to take down all three southern hemisphere sides in one calendar year, with Best at the helm. "It could be quite a day for him," enthuses Easterby. "He has been excellent. He has captained the team to some things that other captains haven't been able to achieve."
Wood was a trail-blazing captain, hauling Ireland from the mediocrity of the last century; O'Driscoll led by example and the example he portrayed was his awesome ability; O'Connell, although wracked by self-doubt, was possessed of an aura that could intimidate and inspire in the same second.
Best has been a different captain, utterly unassuming yet no less lauded by those closest to him who see in his extraordinary devotion to his profession, decent manner and quiet, brooding confidence, somebody who everyone can relate to.
But there was a time when Best felt he was undervaluing himself, too, and that led to an epiphany which, without it, would not see him leading out one of the best professional sides in Ireland's rugby history.
That day in 2005 was a nadir for Ireland and a less than propitious beginning for Best in green.
But he wasn't ready for the international game. To be frank, he looked more like a prop than a hooker.
We recall the mirth amongst the famously unused bench players on the 2006 New Zealand tour when a cry of "Best, get ready" came from the sideline in Auckland.
As Rory stripped, he realised that it was actually Neil, his Ulster flanker namesake, who was being summoned. Nine call-ups. Eight minutes. Three caps.
Was this it? He needed to change, lose a few kilos, change his body shape.
He got the weight down, bulked up, developed ball skills with Matt Williams and Neil Doak at Ulster and developed into a serious contender for an increasingly injury-prone Jerry Flannery.
In the autumn of 2006, he started two of the three Tests this time, and scored his first international try before breaking into the Six Nations side as a first-choice. But the gradient wasn't smooth.
Off the pitch, his perilous beginning to his international career afforded him the opportunity to look beyond rugby, too, for the operation on his neck in 2009 could have ended his career.
Raised on a 900-acre farm in Poyntzpass, Best had just married Jodie and knew he needed to develop some sense of security for a future family.
Developing a passion but also a design for life after rugby, he bought 60 Aberdeen Angus cattle; he sells the breeding stock into the dairy sector. He also grows spring beans.
"It's a great release," he says of his farming life. "I forget about all the idiots I have to deal with playing rugby!"
Rugby - like farming - was bred into him. Dad John was a Banbridge stalwart; he, Rory and another brother, Mark, once played in the same team; Simon would go on to prop for Ireland, alongside Rory, before a heart condition that surfaced at the 2007 World Cup prematurely ended his career, aged just 27.
Always lurking behind Best's cheery façade is the realisation that careers - and lives - can end so suddenly. That vulnerability drives him to ceaseless quests for improvement; it evicts complacency.
All the while, Best worked tirelessly to maximise his talent; attitude was king.
On the farm, he fabricated a throwing device, cutting down and welding an old harvester which can throw anything up to 80 balls back at him during practice sessions.
His devotion to the very essence of self-improvement has made him the player that he is today.
A hooker must, as Joe Schmidt reminded us this week, hit a minuscule target with unerring repetition under intense pressure; he must throw the ball 15 metres to a moving target about 700 millimetres wide and three-and-a-half metres from the ground.
Legacy drives him. He envied Anthony Foley lifting the Heineken Cup with his son and grieved when he was taken.
"It frightens you. I have three kids of my own. It shows you never know what is around the corner.
"You see his legacy and begin to question your own legacy.
"To leave Ulster with just one trophy would be a shame when you see what he achieved with Munster.
"You start to appreciate it more, you realise it won't last forever. As long as I enjoy it and the body feels good, I'll keep going. As long as I feel I can compete, I don't want to be scratching around looking for clubs.
"I hope I will know I'm near the end because my body will tell me. I don't want to be a bit-part player, I've been an integral part of Ulster and Ireland for a few years and that's the way I want to stay.
"There are days it feels more like a job than a hobby. But there's nothing quite like the buzz you get leading your country."
He will feel that buzz again today; he hopes, too, at a World Cup. The best is yet to come.