From http://en.wikipedia.org/wiki...: The Mesoamerican ballgame or Ōllamaliztli in Nahuatl (Nahuatl pronunciation: /oːlːamaˈlistɬi/) was a sport with ritual associations played since 1,400 B.C.[1] by the pre-Columbian peoples of Ancient Mexico and Central America. The sport had different versions in different places during the millennia, and a newer more modern version of the game, ulama, is still played in a few places by the indigenous population.[2] The rules of Ōllamaliztli are not known, but judging from its descendant, ulama, they were probably similar to racquetball,[3] where the aim is to keep the ball in play. The stone ballcourt goals are a late addition to the game. In the most widespread version of the game, the players struck the ball with their hips, although some versions allowed the use of forearms, rackets, bats, or handstones. The ball was made of solid rubber and weighed as much as 4 kg (9 lbs), and sizes differed greatly over time or according to the version played. The game had important ritual aspects, and major formal ballgames were held as ritual events, often featuring human sacrifice. The sport was also played casually for recreation by children and perhaps even women.[4] Pre-Columbian ballcourts have been found throughout Mesoamerica, as far south as Nicaragua, and possibly as far north as what is now the U.S. state of Arizona.[5] These ballcourts vary considerably in size, but all have long narrow alleys with side-walls against which the balls could bounce. - Son of Groucho

Fourth picture shows human sacrifice in connection with the ballgame at Chichen Itza. - Son of Groucho