<Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (July 2007) (Learn how and when to remove this template message) </Td> </Tr> <P> A comparison between American football and rugby league is possible because of their shared origins and similar game concepts . Along with Canadian football, rugby league is the most similar sport to American football . Both sports involve the concept of a limited number of downs / tackles and scoring touchdowns / tries takes clear precedence over goal - kicking . </P> <P> Generally, American football games last much longer than 80 - minute rugby league matches . Because the field is reset after each tackle in American football, it is much slower - paced than the more hectic rugby league, in which play stops for only as long as it takes the tackled player to get back to his feet and return the ball to play . Another major difference is that only the player with possession of the ball may be interfered with in rugby league; defending players interfering with any other attacking player (and vice versa) will incur a penalty . Passing in the two sports also differs: while backward passing is common to both sports, in American football players are allowed to throw the ball forward in certain situations whereas in rugby league forward passing is always illegal . Rugby league players have to kick the ball or run it forward to advance it downfield . To score a try or touchdown in rugby league, the player has to push the ball directly onto the ground once in the try zone, whereas in American football the player has to simply cross the line . American football also requires its players to use a large amount of protective equipment, including helmets, gloves and padding around the body, whereas protective clothing is much more minimal in rugby league, usually amounting to light padding (if any) and soft head gear (hard helmets being illegal). The major difference between rugby league and American Football (Gridiron) is rugby fields are 100 metres where American football is 100 yards . </P> <P> Both sports descend from the older game of rugby football in the 19th Century when its two offshoots developed . British colonists and the British military in Canada brought football to North America . It became popular in American and Canadian universities and prep schools . At the time, association football and rugby football were not as differentiated as they are now and teams would negotiate the rules before playing each game . The sports of American football and Canadian football evolved from these intercollegiate games . </P>

What is the difference between rugby and american football
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