Blight never decoded the meaning of that moon. Maybe it was an obscure reference to JFK's speech, in which he said America chose to fly to the moon not because it was easy but because it was hard. Anyway, it stuck with Riewoldt, who spent his entire career choosing to do what was hard, exhausting himself at last in his 17th winter.

"I wish I could say that I never took it too seriously," Riewoldt said, "that I never took myself too seriously but that's just a lie - I did. I've been an intense person because I've felt that I've had to be. Lately I have questioned myself and thought, I wish I had have enjoyed that a bit more. But then, if I had that mentality, I might not have been the same player."

Riewoldt's closest friend, Brendan Goddard, said, "He always wanted to talk about his feelings and emotions, but he was no doubt one of the most mentally tough players I've ever played with. He just had a will that very few others have had. That's what separated him from ordinary players.

"Grant Thomas laid those foundations," Goddard explained. "That's why we both talk about him so much. He was a second father figure to us. Tactically he wasn't a great coach, but psychologically he was the best. He was always digging deeper."

Not many players of Riewoldt's status have shared such an open, and mutual fondness for their coaches. He speaks glowingly of Ross Lyon, and Grant Thomas, his two long-term coaches who rode the demons with him through the height of his career. His relationships with them are in some way an outcome of his commitment to maximum effort - something all coaches cherish - and also his intellectual curiosity.

Grant Thomas had Riewoldt believe in the idea that football, through the player, could reveal the man.

"Nick and I talked about how football is not really about football," Thomas explained, "but that it's really a reflection of who you are, and what you are. He really resonated with that idea. He wanted to be known as a relentless, professional player, and person."

And there was seldom a match in Riewoldt's career in which he failed to project the qualities he longed for in himself. He went to extraordinary lengths to find consistency, and to find in his mind a place to suffer and be rewarded for it.

"Once I knew I could burn opponents with effort," said Riewoldt, "all of my mental preparation just became about going to the well - being able to dig deep and do that. I had raw ability too, but then so did a lot of blokes."

Thomas believes the legend of Riewoldt "burning" opponents is merely an outcome of his desire to win the ball, and the fact that Riewoldt mostly used athleticism to do it. He's taken more marks than any player in the recorded history of the game.

"I don't see Nick as a natural player," said Thomas. "Firstly he's an athlete, and secondly a highly skilled one. You talk about other great players like Wayne Carey or Gary Ablett, and they are natural players first, athletes second. Nick didn't have great natural skills but he relentlessly put himself into positions to win the ball. He had the most voracious desire."

Bob Murphy, whose career has spanned the same two eras as Riewoldt's, spent more time than most players observing him in opposition.

"I always thought of him as a giant, pumping heart on horse legs, willing himself to the ball again and again to satisfy a deep sense of hunger in his soul," Murphy said. "It was intimidating to witness up close."

All sports people are motivated to a large extent by their fear of failure. It's the most simplistic explanation and, in a way, the most honest, since it addresses directly what affects all performance - the ego.

"Fear of failure has always been my motivator," Riewoldt said. "I've never felt fully comfortable because every week is an opportunity to either enhance your reputation or diminish it."

Riewoldt was famous for his daylong warm-ups, which were a product of his fear more than they were any study in how to properly prepare for elite performance.

"The warm-ups became a bit of a monster," Riewoldt explained. "It became something that I needed to do because it was delivering results. I just had a lot of nervous energy, and always thought I needed to get out of my comfort zone to be mentally ready to play. I'd go for a run in the park even before I left home. Then I'd go to the ground and do the same thing. That's what game day would do to me - I'd be sprinting up the wings two hours before the game."

His has been a pure, but exhausting way to play. After nearly two decades of complete effort, no one in football has better earned a place to rest. It's quite incredible that Riewoldt could have survived for this long after those grand final losses, and managed to cup that flame inside against every easy wind that must have blown his way.

Relative to what can happen to a body on the football field, Riewoldt's magnificent limbs have been good to him, allowed him to stay on and keep running. He had a chunk of medial cartilage removed from a knee in his first year of professional football, which tends to age the joint at an advanced speed.

That joint went rogue in 2012 and '13, and nearly broke him. He was having it aspirated (drained by needle and syringe) every week, a rather crushing exercise for an athlete, who knows the moment he leaves the doctor's office that the fluid is beginning to refill the joint.

"That was the only point I thought, 'I can't keep doing this'," Riewoldt said. "It really took a toll on me mentally. Then for some reason it just settled a bit. The doc said the inflammation response sort of burnt out for a while. But it's reached a point now where I can't change direction. Once I get a head of steam up, and the boys miss me by a metre, there's no adjustment anymore. I am a tram."

Like every great sportsperson before him, Riewoldt must now face the psychological wasteland of retirement, a new but frustrating challenge. He assigns to football history, and to his own private lament, a drawn grand final and two that were lost outright. These were the most dramatic moments of his playing career, the ones that promised the most joy and purpose and failed to deliver them.

"I do think about it quite often," said Riewoldt. "Especially when I watch the Super Bowl in the States every year and see the players lift the trophy - just the euphoria of it. What I really would love to be able to look back on is having tasted that euphoria, and having shared it with the fans. I wish I had a photo of my family with the cup. To think of how much fun that would've been, to celebrate that with my family, my whole family."

Both he and Brendan Goddard have consoled each other in the years since those grand finals, sometimes by talking about "what could have been" and other times via the shared knowledge that they did everything possible to win them.

"In a sense we got as close as anyone has ever gotten without winning it," Riewoldt said. "In 2009 we lost three games by a cumulative total of 17 points. 2009, to me, is the year we should have won it. We dominated that season. In the grand final we dominated clearances and inside 50s but didn't convert on the scoreboard. It is what it is - a bit of it luck, a bit of it execution.

"But I would argue that the group that played together through that period have relationships that are as strong as premiership teams," Riewoldt said. "That sense of shared experience and going into battle together. We've got everything but the cup, and the adulation, the memories ??? but I choose not to be bitter about it."

Despite having given himself entirely to football, Riewoldt says he is not afraid of what's coming.

"I've got as good a perspective as anyone in this situation could have, I think. I've been exposed to the other side of the world. And I've experienced loss, and grief."

The loss and grief to which Riewoldt refers is the loss of his younger sister, Maddie, who died in 2015, and in whose name Riewoldt helped to start what is already a successful foundation.

"To a degree, it (grief) changes you to your core," Riewoldt said. "Everything you thought you knew, the way you imagined life panning out for you and your family is just flipped on its head.

"At times it feels way too easy to just keep living. Life just rolls on, and keeps happening around you. That was probably the hardest thing, to see life just keep going."

And so Riewoldt himself must keep going, out into the world, a new father, and a man possessed of the great inner knowledge acquired through such a physical life.

"I know it's the right time for me to leave, but I also know what's coming," he said. "I'm aware that a loss of identity is coming. This is the first time in my life that there's uncertainty but I'm very driven, and I'm a competitor. I think maybe it'll help that I've been going to the states every year with my wife (a Texan), where my identity is stripped back and I'm just Catherine's husband."

Riewoldt will be remembered as a thoroughbred, a footballer of pure heart. It's a hard thing to write about because the words required to describe him are words familiar to every footballer. They adorn the walls of every country club and league in Australia.

They're the words inscribed on the plaques and boards that people touch, and sign, and make promises about as they run down races into the cold light of winter. The same light in which Riewoldt proved those cliches, and brought them to life on his long leads, in his straight lines and his heaving, breathless desire for more.

The game won't be the same without him, and that may be the greatest accolade of all.