The national sport in Argentina is called "El pato" (the duck), but most of the population of the country don't know it. It's a game that the "gauchos" used to play. Many years ago (I think more than 100 years) the players didn't use balls, they used to play with a real and alive duck as the ball. The game is like "Polo". Now in the actuality of course they don't use ducks anymore, they use a normal ball (thank God). And that's why they named the game "Pato".