However you measure it, Gianluigi Buffon is one of the greats

The thing about legendary athletes retiring is that you know it's coming. And yet -- regardless of whether they ride off at the peak of their powers or stick around, driven by the desire to squeeze as much as they can (even on a descending arc) out of the sport they love -- you still feel a little unprepared when it happens.

So how do you begin to contextualize the career of one Gianlugi Buffon? You can do it through numbers; just choose your poison.

- Italy, Juventus great Buffon retires at 45

Longevity? Twenty-eight years and four different decades (Diego Maradona was still playing when he made his debut and he witnessed the beginning and the end of Cristiano Ronaldo and Lionel Messi in Europe).

Appearances? He's in the top 10 for international caps in the men's game and ranks first all-time in Serie A.

Trophies? Eleven league titles (including two of the ones he won at Juventus, which were later revoked due to the club's Calciopoli scandal), six domestic cups, a UEFA Cup and, of course, the biggest prize of them all: the 2006 World Cup with Italy.

Transfer fee? When he moved from Parma to Juventus in 2001 he set a transfer record for goalkeepers ($50m at the time) that would stand until 2018 and which, when adjusted for inflation, would still be a record today.

You can do it through moments. Like his club debut at 17 years of age back in 1995, when Parma threw him in to face AC Milan and he made a string of stellar saves off guys named Roberto Baggio and George Weah.

Or his international debut at 19, coming off the bench after half an hour in a blizzard away to Russia in a crucial World Cup qualification playoff. Or his first Champions League final, in 2003, when he almost single-handedly kept Juve in the game with saves like this one against Milan before capitulating on penalties.

Or, in fact, the save from Zinedine Zidane's header late in the 2006 World Cup final (there's a parallel universe in which Buffon doesn't make the save, a frustrated Zidane doesn't headbutt Marco Materazzi moments later -- and therefore doesn't get sent off -- and the Frenchman retires with another World Cup and another Ballon d'Or).

Or the decision to stay at Juventus -- unlike Zlatan Ibrahimovic and Lilian Thuram -- after their enforced relegation following the Calciopoli scandal.

Or the emotional choice to return to the second division with Parma, where it all began: he didn't get the promotion he hoped for. In his final game, he came off injured at half-time of their promotion playoff against Cagliari with Parma 2-0 up (they would eventually lose 3-2 on aggregate), but he did record his 500th clean sheet.

There were bad times, too. Like his well-chronicled bouts with mental health issues, to his red card for manhandling referee Michael Oliver after a penalty was awarded in the dying minutes of a Champions League quarterfinal against Real Madrid. But he spoke openly about his bouts of depression and panic attacks, something few athletes (let alone ones dubbed "Superman") do at the top of their game.

And while the Oliver incident was a stain -- for which he later apologized -- he did have a neat turn of phrase post-match: "If you give a penalty like that in that moment, it's cruel and heartless... it means you have a trash can where your heart should be."

Buffon was the synthesis of three qualities that make a difference at the highest level of sports, any sport: athleticism, work ethic and personality. Genetics play a part, of course. His mom won three Italian titles in the shot put and discus, his dad was a competitive shot putter too, his sisters played professional volleyball, his uncle played professional basketball. The result? A keeper with outstanding reflexes who moved his 6-foot-4 frame with the ease and grace of a much smaller man.

The work ethic played a huge part in keeping him going into his mid-40s and that may have been a surprise to those who knew the young Buffon as a midfielder (a position he played until he was 12) because, as the story goes, he opted to play in goal (like his idol, Cameroon goalkeeper Thomas N'Kono, in whose honour he named one of his kids) because he didn't like running around in the hot sun.

But Buffon also stood out for the meticulous way he studied opponents, for his sense of positioning -- something he worked on incessantly -- and for the way he adapted his game (not least his kicking) as the needs and requirements of the position changed over the decades.

And then there's the personality. Both the mental strength to use mistakes -- no, he was not infallible -- as learning opportunities and to shrug off errors until after the final whistle. But also the charisma to lift teammates, to "say the right thing at the right time to the right person" as his long-time teammate Giorgio Chiellini put it.

Where does Buffon rank in the pantheon of keepers? Many would probably have him at the very top or very close to it: as with all things, that will be open to debate. What's less debatable is that you'd be hard-pressed to find a figure who loomed as large -- both metaphorically and in real life -- between the sticks.

"I've always been a dreamer, from the time I was a toddler to right now," he said recently. "I was blessed that I was given the tools to turn some of those dreams into reality. Now that I'm grown up, I still feel like dreaming."

Buffon's next dream? He's reportedly been tapped to replace the late Gianluca Vialli as head of the Italian national team, working alongside manager Roberto Mancini. Given the nightmare of Italy's failure to qualify for the last two World Cups, you can guess what his next dream will be.