Gerard Pique once said that Cristiano Ronaldo was the best of the humans, but Lionel Messi was an extraterrestrial. Pique, the Barcelona defender, was right.
Messi's presence did seem otherworldly, an alien who crash-landed in Argentina and was scooped up by Spanish guardians. He possessed powers beyond ordinary folks, as long as he kept on his Barcelona jersey.
When he swopped his club costume for the colours of his country, Messi's magnificence was somehow muted on the loudest stage. The World Cup confirmed his mortality. He was just a man, a first footballer among equals.
He still can't quite escape the asterisk, the "nearly man" tag, the sense of "almost, but not quite". He's the world's greatest player, but he's never been the greatest player at the World Cup. He hasn't even been close.
Brazil offers the final breakthrough. Messi turns 27 during the tournament. This is arguably his last chance to outrank them all.
Argentina's little genius is already on the podium, but he still looks up at Pele and Diego Maradona, not because they were blessed with superior talent - they weren't - but because they won the World Cup.
The tournament does more than separate men from boys; it distinguishes men from Pique's extraterrestrials.
Pele peaked in 1970. Maradona was made in 1986. Their club careers didn't always scale the heights of their contemporaries, namely George Best, Alfredo di Stefano, Johan Cruyff and Michel Platini.
But Pele and Maradona reached Everest. In 1970 and 1986 respectively, they wept, literally, for there were no more worlds to conquer. Everything else was immediately dwarfed in comparison; lesser achievements worthy of respect, but not reverence.
Messi still has one more mountain to climb. He will hope this is third time lucky.
In 2006, he was the new kid on Barcelona's block, recovering from injury and not quite ready to be entrusted with the keys of his country's kingdom.
By 2010, Messi defied the naked eye and computer game pixels. He did things beyond the capabilities of PlayStation footballers.
His dribbling, perpetual foot-prodding technique confounded scientists. Human feet were not supposed to move that fast. His incessant tapping belonged to a different species, seemingly stolen from a Woody Woodpecker cartoon.