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
Comparison of American football and rugby union only one of the three being on the field at a time. That is to say that in professional American football, the majority of players play in only one specialization (or "one side of the ball") – however, every player is eligible to play in any specialization. In rugby the teams are divided into eight forwards and seven backs. Both groups of players partake in attacking and defensive plays and are on the pitch at the same time. Only the eight forwards take part in the "set pieces", which are ways to contest ball possession when there is a minor