How Uruguay, a nation of three million, punches so far above its weight in football

In each episode of The South America Files, we'll be exploring how the game has developed in the different countries of the continent; the clubs, the players, the joys and despairs. Guided by South American football expert Dr Pete Watson, this time, we're off to Uruguay - winners of the first World Cup and unbeaten in the competition for more than 20 years. How have they remained a powerhouse despite their modest size?