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When Spain won the 2010 World Cup final at Soccer City in Johannesburg, the team featured seven alumni from Barcelona's youth academy, La Masia—current club captain Andres Iniesta, Carles Puyol, Gerard Pique, Xavi Hernandez, Sergio Busquets, Pedro and second-half substitute Cesc Fabregas.

Several months later, Iniesta and Xavi joined Lionel Messi, the academy's most famous graduate, one of 546 since its inauguration in 1979, as per FC Barcelona's press department, on the Ballon d'Or podium (where Messi picked up one of his five gongs). It was a moment that captured the football world's imagination.

How could a single football academy churn out so many great players? It has surpassed the feats of previous golden generations like Manchester United's "Class of 92," Ajax's youthful 1995 Champions League-winning team and a contemporary one—Sporting Lisbon's academy, which provided 10 of the 14 players who helped Portugal to Euro 2016 glory at the Stade de France, per the Daily Mail.

La Masia's vaunted production line is slowing down, however. It still provides more first-team squad players for its club than Real Madrid's youth academy, La Fabrica, or "The Factory": 12 compared to seven (2007-2008); 11 to seven (2008-2009); 11 to four (2009-2010); 12 to six (2010-2011); 11 to five (2011-2012); 17 to five (2012-2013); 17 to nine (2013-2014); 12 to seven (2014-2015); 12 to seven (2015-2016); and 10 compared to nine this season.

Fewer of Barcelona's graduates make it to the front line, though. If you exclude Sergi Roberto, the last current player to emerge from La Masia onto the first team as a regular starter was Busquets. That was in 2008.

In comparison, Dani Carvajal, Casemiro, Nacho, Alvaro Morata, Kiko Casilla and Lucas Vazquez—who have all sprung from La Fabrica—have played prominent parts in Real Madrid's push this season to win La Liga and to become the first team to retain the European Cup since Arrigo Sacchi's Milan team in 1989-1990.

Real Madrid's graduates also do better than Barca's in hooking up with clubs around Spain. This season, 41 players from La Fabrica are playing with squads in the premier division of La Liga compared to 30 from La Masia, a ratio that is repeated in the second division of La Liga: 28 (Real Madrid) and 21 (Barca), as per Guia Marca De La Liga 2016-2017.

The framework of both clubs' youth academies is alike. Both start recruiting players at seven years of age. While Real Madrid only focuses on football and basketball, Barça has 76 residents living at La Masia, drawn from a number of sports: football (52), basketball (13), futsal (4), roller hockey (2) and handball (5), as per Barca’s press department, plus about 180 boys who live at home and train at the club, most of them aged 13 and under.

Real Madrid has about 300 footballers enrolled at its academy, where they live in-house for an average of three years. The annual cost for a young player's schooling and accommodation is between €35,000 to €40,000, excluding the maintenance costs for the club's training facility at Valdebebas, as per Steven G. Mandis in his book The Real Madrid Way: How Values Created The Most Successful Sports Team On The Planet.

The annual budget for La Masia is €30 million, according to Harvard Business School’s 2015 report, Futbol Club Barcelona, which also notes that Barcelona has the highest rate of 18-19-year-olds (50 per cent) studying at university among top European clubs.

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Barca is a victim of its own success. There is no room for younger players to supplant the likes of Pique, Busquets and Iniesta, which came to harsh light in 2013 when the club sold a crown jewel, Thiago Alcantara—who had been earmarked as a successor to Xavi in the first team's engine room—to Bayern Munich.

There is such pressure, too, to maintain its status as one of the world's greatest teams that it is spending heavily on the transfer market, having coughed up €343 million over the last three years, as per Marca, most notably on Neymar Jr. and Luis Suarez. This short-termism is something that concerns Victor Font, who ran for president of FC Barcelona in 2015.

"Luis Enrique, like most coaches, has been more concerned about the short term, about results today and tomorrow, rather than making sure the youth system, the club's foundations, continue being built," he says. "That has not been his mandate. He has been much more pragmatic. If he needed to sign someone from the outside instead of giving a chance to someone coming from within, he did that if it secured short-term success. He hasn't bet in the same way that, for example, Pep [Guardiola] did or Johan Cruyff also did in the past with youth-team players."

During his four-year reign as Barca coach (2008-2012), Guardiola was adept—and courageous—in regenerating his squad from within. He gave several players—including Busquets, Pedro, Roberto, Thiago and Marc Bartra, who is now part of Borussia Dortmund's central defence—their starts in Barcelona's first team.

Guardiola was an ideologue. He adhered to his philosophical principles, as Real Madrid's former manager and World Cup winner Jorge Valdano told Simon Kuper for the Financial Times, "to the point of exaggeration."

Barca has abandoned Guardiola's obsession with midfield dominance. Under Enrique, its chips are loaded heavily on its front three stars—the MSN of Messi, Suarez and Neymar—producing moments of magic to decide matches rather than the pass-and-move way in which Barca used to suffocate teams under Guardiola.

Font argues that Cruyff's (and Guardiola's) attacking possession-based interpretation of football—which stretches back over three decades and through all its teams, from under-8s to first team—is secure. It is enshrined in their teams' style of play. He is worried, however, that Barca is falling behind in the science and technology of player development, including training methods and strength and conditioning, mentioning Manchester City and Shakhtar Donetsk in the Ukraine as two of the most innovative youth academies in global football.

"I fear that we are not adjusting ourselves and making sure best practices are being applied across the youth system of La Masia. I have insights from within that this is not 100 per cent happening.

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"FC Barcelona has traditionally been run more like a social club, like a tennis club. You cannot go to our members, who own the club, and talk to them about mid- to long-term risks, about things in the foundation of the football system, which are very difficult to see in the day to day, when you have Messi and Neymar in your team winning league titles and the Champions League. It's like when you go to the population and talk to them about climate change. People look at you [like] 'What are you talking about?'"

A noticeable shift in spending practice has occurred between the clasico rivals, who play against each other at the Santiago Bernabeu over the weekend. A result for Real Madrid, which leads Barca by three points with a game in hand, would put it on the home straight for a first league title since 2012.

It used to be that Real Madrid was renowned for spending big on rejuvenating the squad, particularly once the galactico era—a policy of jamming the team with the world's most glittering attacking talents, like Luis Figo, current first-team coach Zinedine Zidane and later Cristiano Ronaldo—swung into life when Florentino Perez assumed the presidency in 2000.

Diario Sport, the Catalan sports newspaper, coined the term "cantera versus cartera" (youth academy versus wallet) to denote the difference in philosophy between big-spending Real Madrid and Barcelona, which placed an emphasis on nurturing homegrown talent. Barca's former president, Joan Laporta, once gloated on Spanish television that Real Madrid liked to buy Ballon d'Or players whereas Barca preferred to make them (h/t Reuters).

Roles have been reversed. Now there is a more balanced, workmanlike quality to Real Madrid's squad. The club only spent €31 million during last summer's transfer window, when it exercised an option to buy back Morata from Juventus. Barca splurged €123 million on six players, as per transfermarkt. Yet only one of them—Samuel Umtiti—has nailed down a place on the team’s starting XI.

It is Barcelona, and not moneybags Real Madrid, which pays its players more. Barca ranks second behind Manchester United in player wage spend, according to Sporting Intelligence's Global Sports Salaries for 2016. On average, Barca's players earn £108,636 a week compared to £97,151 for Real Madrid's.

It seems that Barca—which is still revered globally for the prowess of its youth academy–has won a propaganda war. Whether it will secure the league title again this season hinges on a win on Sunday at the Bernabeu and Real Madrid slipping up in at least one other league fixture in their run-in, which is unlikely given the strength in depth of their squad.

Follow Richard on Twitter: @Richard_Fitz

All quotes and information obtained firsthand unless otherwise indicated