"David Beckham is Britain's finest striker of a football not because of God-given talent, but because he practices with a relentless application that the vast majority of less-gifted players wouldn't contemplate"
-- Sir Alex Ferguson
How to measure football's "Beckham effect."
There's obviously the money -- approximately $46 million earned by the midfielder in 2012 alone, according to Forbes -- and the celebrity status that good looks and a Spice Girl wife will inevitably bring.
Then there's the five-year missionary trip the sport's most-recognizable figure made to North America in 2007.
More than 700 media accreditations were handed out upon his unveiling as a Los Angeles Galaxy player, and after a half-decade, two titles and increased attendances and exposure for Major League Soccer, there were still some who questioned whether The Beckham Experiment, as Grant Wahl called it in his 2009 book, had actually been worthwhile.
Personally, I've always left those sorts of questions to the accountants and cultural critics who happen to dabble in sports every now and then, typically whenever an athlete is generating so much puff it requires spreadsheets and analyzing from a popular culture perspective.
To me, David Beckham -- who will retire at season's end -- is a footballer, plain and simple. And anyone who has ever questioned the man's resilience, professionalism and adaptability has ended up eating crow.
The English media establishment, whose hysteria in blaming the then-Manchester United winger for the Three Lions' World Cup exit in 1998 led to his being burned in effigy across the country, got a taste of it three years later when Beckham put the team on his shoulders, scored against Greece and hauled them into the 2002 finals.
And Landon Donovan got a sizeable helping after he questioned his Galaxy teammate's commitment in Wahl's book, opining that Beckham was "not a leader... not a captain," then adding in a bizarre statement that Beckham had "better be picking up meals, too, or else I'll call him out on it."
Donovan didn't call him out on anything, and in a way his irrational jealousy -- likely born out of his own futile attempts at fashioning a career in European football -- is a microcosm of all the resentment that has ever been aimed at the former England captain.
But I think the clearest picture we have of Beckham the footballer was captured in 2007, when he was dropped from Fabio Capello's Real Madrid team after the Christmas break.
Only four months prior he had been omitted from Steve McClaren's first England squad -- once again scapegoated for a World Cup failure -- and heading into the second half of the season it looked as though there wouldn't be much football for him to play.
So he got down to work.
Having kept up his fitness in training, he was recalled by Capello for a Feb. 10 match against Real Sociedad. He scored in the game, and over the next few months helped the Spanish giants climb from third place to first in La Liga, eventually winning the title.
"I told David the other day that I thought he has never been in such good form, either mentally or physically," Capello said at the time. And then, a hint for McClaren: "I can't understand how a player who is playing so well can be left out of any national side."
Beckham was recalled to the England setup the very next day. And in his international return he provided an assist on John Terry's opener against Brazil.
Four-and-a-half years later, having played through a hamstring injury en route to winning the MLS Cup, Beckham lifted Donovan off the ground in celebration.
In his post-match remarks the American praised Beckham's demonstration of steel -- sentiments echoed later by Galaxy manager Bruce Arena, who referred to the newly-crowned MLS champion as "a great teammate, a great person."
Donovan, Capello, McClaren and countless others -- they all ate crow.
And while they picked the humility from their teeth, Beckham went about his business with a quiet dignity, working hard and winning trophies wherever he went.