If there’s been a dominant trend in the first week of the 2018 World Cup, perhaps it has been how well European nations from beyond the continent’s traditional giants have performed. Iceland, Switzerland, Serbia, Sweden, Croatia and Russia are all off to a strong start.

This should be no surprise.

Only two nations from outside Europe and South America have made the World Cup semifinals (the United States in the inaugural competition in 1930 and South Korea in 2002 ). In 20 previous World Cups, only 12 countries have reached the final — all from Europe or South America — and only eight sides have won the tournament. Since 1950, only nine teams from outside UEFA (European soccer’s governing body) and CONMEBOL (South America’s) have reached the quarterfinals.

As soccer became more global, more diversity among the most successful teams was expected. Pelé famously predicted that an African nation would win the World Cup by 2000. The first edition of “Soccernomics,” a soccer statistics book published in 2009, also predicted that the countries that dominate soccer would become more diverse.

And in the final decades of the 20th century, the gap between Europe and South America and the rest did become less pronounced, as experience, infrastructure and playing numbers increased in the rest of the world. But then, the trend went into reverse. Since 2002 — when South Korea reached the World Cup semifinals — soccer’s traditional power centers have reasserted their dominance. All 12 teams to reach the semifinals of the World Cup since 2002 have been from either Western Europe or South America. The semifinalists have been from nine different countries; these regions do not merely have a few elite teams, but a depth of formidable sides.

In a recent study of global soccer, researchers Melanie Krause and Stefan Szymanski, one of the authors of “Soccernomics,” recorded the results of all matches between national teams from other soccer confederations — AFC (Asia), CAF (Africa) and CONCACAF (North America, Central America and the Caribbean) — and teams from Europe and South America from 1950 to 2014. Looking at four-year cycles that end with the year that a World Cup is played, they found that the traditionally less successful regions improved their performance (measured by win percentage) against teams from Europe and South America between the 1971-74 cycle (the first one analyzed) and the 1999-2002 cycle. But since then, their results against these two continents have declined.

The Krause and Szymanski study, which was released in December, did not look at the 2015-18 cycle, but the trend appears to be continuing — at least at the major tournaments. In 2016, the best of South America played the best of North and Central America in the Copa America Centenario. In that event, CONCACAF teams had a 33 percent win rate against CONMEBOL teams in 18 cross-confederation matches. Through Day 7 of the 2018 World Cup, Europe and South American teams have a 12-3 record against those from Africa, Asia and North/Central America.

In Europe, the dominant soccer countries from 1950 to 2004 (with the exception of the brilliant Hungary side of the 1950s) traditionally came from the core of the most economically integrated European nations — France, Germany, Italy and the Netherlands (which were all among the founding members of the European Economic Community, the forerunner to the European Union, in 1957). In recent years, however, the excellence has spread. Since 2004, the southern European nations of Greece, Spain and Portugal have all won the European championship. Also since then, Spain has won the World Cup, and Portugal has reached the semifinals.

Over the past 40 years, perhaps the most significant change in the international soccer hierarchy has been how much the lesser European teams have improved. Krause and Szymanski calculated the performance (win percentage) in international soccer of a sample of 76 countries with populations of over 1 million since 1975. They found that even though the European nations ranked the highest (based on win percentage), on average, in the 1975-86 period, they collectively improved their ranking in the 2003-14 period. South American teams also saw improvement. But the average rankings of African and CONCACAF teams declined, while those from Asia remained stagnant.

The researchers also evaluated how the nations for each region that ranked the worst in the earlier years progressed over time. The European countries that were in the bottom half of the world rankings in the 1975-86 period improved dramatically in the 2003-14 period — going from an average ranking of 53 to 38. Those African teams that were previously in the bottom half of the world rankings saw their positions worsen, going from an average ranking of 51 to 52. Before, this group of African nations had been ranked slightly higher than their equivalent in Europe; by the second time period, they were fully 14 places behind. “The biggest beneficiaries of worldwide convergence have been second-tier national teams from Europe and South America,” Krause and Szymanski write.

While South America has developed unique advantages — the vibrancy of its soccer culture and unstructured grassroots play are probably more common than anywhere else in the world — European nations have benefited from the growing concentration of the best players and coaches in its big leagues, meaning that young players from these countries enjoy remarkable learning opportunities. The European national soccer associations also generally have the most cash and the best organization, which, in an era of hyper-professionalization, is increasingly important. And, as Europe and South America have the strongest federations, weaker teams in these continents benefit from playing the best opposition, enabling them to learn and improve.

Consider Iceland — a country of only 330,000 and the smallest nation ever to qualify for the World Cup. In its first game, it drew with Argentina. Once, Iceland’s players could train only six months a year because of the brutal winters. But in 2000, the Iceland football association opened the country’s first indoor soccer facility. In the years since — using a combination of government funding and money from UEFA — Iceland has built more than 100 all-weather artificial surfaces for schools, with floodlights and under-floor heating. To give young players the best coaching, Iceland invested in creating UEFA coaching courses at home; before, coaches had to go to England to train. There are now over 800 coaches with UEFA licenses; from the under-10s upward, all coaches must hold a UEFA-B qualification. The generation that has benefited from these revolutions, in facilities and coaching, has risen more than 100 places on the FIFA world rankings since 2012 and reached the quarterfinals of Euro 2016, Iceland’s first ever major tournament.

Krause and Szymanski suggest that countries from beyond Europe and South America suffer from soccer’s equivalent of the middle-income trap. The national boards can learn from old best practice in the two powerhouse continents — in areas like fitness, nutrition and training — and improve their standards. But they lack the cutting-edge infrastructure, talent ID programs, sports science or elite coaching to rival the best nations.

What has happened so far this World Cup — with European teams excelling and those from Asia and Africa floundering — is really in line with what was expected before. Indeed, if the 32 teams in the World Cup were determined by FiveThirtyEight’s pre-tournament Soccer Power Index rankings, there would be only three African representatives, two from CONCACAF and one from Asia. While soccer is a genuinely global sport in its reach, it remains a long way from being one in terms of its competitiveness.

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