Comparison of American football and rugby union possession of the ball at their own 20-yard (25 yard line in College Football) line. An important difference between the two sports involves the aftermath of a score. In American football, the scoring team kicks off, except after a safety. In rugby union, the team conceding the score kicks off (in rugby sevens, a variant of rugby union featuring seven players per side, the scoring team kicks off). An American football team consists of an offensive unit, a defensive unit and a "special teams" unit (involved in kicking and kick returns). Only eleven players can be on the field at
American football at the Summer Olympics "by default." As Francis Field was the main stadium for the 1904 Summer Olympics, only those games would have been considered a demonstrations for Olympic crowds. Only two games at Francis Field were played that did not involve Washington: a match between Purdue and Missouri, and the first match between two Indian school teams (Haskell and Carlisle) who were considered powerhouses in college football at the time. Though American football has not been played in the Olympics since then, various American football players have participated in the Olympics. In 2013, The International Olympic Committee gave provisional recognition to The International