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RIO DE JANEIRO – Lionel Messi's life has been built toward this moment from childhood, even before he knew it himself.

Sunday's World Cup final isn't the last step of the journey, not at 27 years of age, not with further paths of domination to tread. But it is the most important step, the seminal one, the one that magnifies everything to 90 or 120 minutes of effort. And everything means just that.

For when Messi faces his ultimate challenge on this ultimate stage, when his Argentina side takes on Germany in this most magnificent of events, he will need to draw on each step, misstep, lesson and twist in the road that has led him to the crossroads of soccer history.

The mightiest of tasks and the stoutest of opponents lies in his path, just as it should be. A World Cup final is not about one man. It is about two countries – heck, all countries – and it's about a game that entrances the planet reaching its pinnacle moment.

It is about subplots, too, and this is the most burning one. Messi, the man with destiny tantalizingly near and with all-time greatness assured, is seeking to bridge the last frontier to immortality.

No one likes to lose or suffer, least of all a warrior like Messi. Yet as he spends the reflective moments leading into a soccer match that is so much more, he may find himself grateful for his past tribulations.

There have been many of them, and they started when he was young.

Messi was not supposed to be a soccer player. He wasn't supposed to even reach five feet tall due to a genetic hormone deficiency that is a mild form of dwarfism.

As a youngster in the Argentine city of Rosario, he was already on the books at local club Newell's Old Boys receiving treatment to accelerate his growth to somewhat normal levels when the cost of the medicine played a significant role in his career.

Neither Newell's, nor leading Argentine club River Plate, would pay the $900 per month required for his medication. Spanish giant Barcelona would, however, and the rest is history.

Friends of Messi say he still carries a chip on his shoulder as a result of his height, or lack of it. He doesn't have short man syndrome, they say; he just wants to prove he can face off against anyone. In a sport where players are often dismissed for being too small, he has turned his diminutiveness into an advantage.

Combined with his flashing feet, an impossibly low center of gravity and the ability to twist and turn, Messi has bamboozled defenses for years. Confronted with men twice his size he makes a mockery of them, making them look slow and lumbering.

The fleet of foot and turn-on-a-dime movement will be needed on Sunday at the Maracana Stadium. Central defender Mats Hummels of Germany is a beast and one of the best players in this tournament, and he would be a realistic contender for the Golden Ball, the award given to the World Cup's best player, if defense was given its due by FIFA.

Standing in Messi's path is a packed and fluid German midfield full of players ready to poach the ball and anchored by the physical presence of Bastian Schweinsteiger. Germany, in case you hadn't noticed, is in no mood to give an inch to anyone.

Perhaps it is fortunate then that Messi still carries with him the pulse of Rosario, where from infancy he learned the game on rocky wastelands and the gnarled streets of Argentina's third biggest city, where the rules of the beautiful game are blurry to say the least.

Part of Messi's learning curve was pickup games against older boys who didn't take kindly to being tormented by a comparative midget with sick skills and inherent fearlessness. In a sport where flopping and diving and theatrics are part of it all, you rarely see it from Messi. Surely, it's a result of those initial years where no one was going to blow a whistle to help you out.

To him, staying on his feet is part of the challenge. It is part of proving himself time and time again. It is part of the fun, part of the battle, and say "You can't take me down big man."

This World Cup has been rougher than any in recent times. There are suggestions that FIFA has urged referees to let things go, keep the flow and intensity of the game for the sake of the viewing spectacle. With everything at stake, and faced with a silk-footed supremo, Germany is going to get stuck in. It would be stupid not to.

When Messi was 12, he left his homeland and joined Barcelona's fabled La Masia academy. It is where generations of talent have been produced – but it is no fail-safe guarantee of stardom. For every superstar, there are dozens who have flamed out and ended up at other clubs and in the lower leagues or out of the game altogether. La Masia provides an opportunity to thrive but it relies on the individual finding the willpower to do so.

For those prepared to listen and learn and ingest the knowledge and refine their skills, there is no better place to be. That is where Messi added edge to his game – a technical, precise edge – to his free-spirited ways. But he also learned that the game is so much more than that. The value of space – enough to perform a turn or a move that can rip open a defense – was instilled in him through daily repetition.

Everyone says Messi is a natural and of course he is. But that is only part of it. The great unspoken truth about him is all those hours of dedication that made him the best. Once he got into the Barcelona team as a teenager, it was quickly built around him and a dynasty followed with six Spanish league titles and three Champions League crowns.

With so much of Messi's education having taken place in Spain, there was for a while some reticence to fully accept him in Argentina. Whenever things did not go seamlessly for the national team, criticism followed. Did he play better for Barca? Did he try harder for them? Was he Argentine enough?

Overlooked was that, as soon as he was an adult, he would return to Rosario each year and that he insisted on keeping the family home he grew up in. Also, there is still a bar there that his family runs as well as businesses that he has invested in. Never mind that Messi always returned for national team duty, always put in the effort, after those long flights from Europe and in sometimes extreme conditions like the lung-bursting altitude of Bolivia.

Argentines get it now. They chant his name – no, they scream it – with pride and devotion, and almost every shirt they wear proudly displays "Messi 10." They roar for him when he produces magic and also when he doesn't. As he dragged weary legs through the semifinal against the Netherlands, he was lifted by a chant from nowhere that quickly spread across Arena de Sao Paulo: "Hail to Messi. Argentina's favorite son. A boy who moved away but was never lost."

Yet for all the glittering trophies in his home there is an empty place in Messi's heart. He doesn't like failure. It eats at him until he can rectify it. He hasn't had to experience it very often.

But he has suffered with Argentina. And he has suffered against Germany. In 2006 he was still a rookie, just 19 years old, and while already anointed as a future great he was not yet experienced enough to carry the burden of a World Cup campaign. He shined briefly in the tournament but was not trusted against the Germans in the quarterfinal, being forced to sit and watch as a penalty shootout ended in an inevitable German win followed by an on-field postgame fight between the two teams.

Four years later, Messi had become the central man, but revenge did not come for Argentina. Instead, it was a nightmare as the Argentines were torn apart by Germany 4-0 again in the quarters in Diego Maradona's final game as coach.

It was then that the doubters really kicked up a storm. Why does Messi not produce at World Cups? Are they tainting his legacy? And, again, does he play better for Barcelona? Never mind that he'd had a solid tournament. Or that the reason for Argentina's demise was pitiful defending and skewed tactics from Maradona, who was a genius during his playing career but hopelessly naive from the sidelines.

That defeat hurt Messi, racked him with deep, wrenching disappointment. He surely knew why it had happened too, knew the tactics were wrong and had left only one realistic outcome.

Maradona is gone now, replaced long since by Alejandro Sabella. Some deride Sabella as a "yes man" to Messi, but his results speak volumes. Here is Argentina, back in the final after 24 years and one win away from the third title in its history.

This is a final that, for all the romance of Brazil and the grit of the Netherlands and all the other storylines and turns, is the right one. These are the two best teams and this is a showdown for the ages.

There are countless factors that go into deciding games like this, but only one truly stands out; Can the will, skill and desire of Messi overcome the clinical game plan designed to thwart him? Can his greatness become legend?

Lionel Messi has made the journey to soccer's summit, lived and breathed every moment of it and sacrificed all in this pursuit. Now he is here with just one more step to go, and he has a life full of experiences powering his twitching feet and ambitious mind.