Tennis polo
The sport is played on a grass field between 80 and 100 yards long and 50 to 65 yards wide. The goal area is a semicircular line with an 11-yard radius and the penalty mark at 13 yards from the goal. An experimental rule has a second semicircular line on the field with a 17-yard radius. Generally, a field for gridiron football or soccer can be used.
Comparison of American football and rugby league
American football is played on a rectangular field long by 53 1⁄3 yards (48.8 m) wide. Near each end of the field is a "goal line", which are apart. A scoring area called an end zone extends beyond each goal line. Yard lines cross the field every , two rows of hash marks run parallel to the side lines near the middle of the field. At the back of each of the end zones, there are a set of goalposts. American football goalposts were formerly H-shaped and were located on the goal line, but; in 1967, the NFL adopted the current modern offset-fork design, made from extruded steel pipes. The goalposts currently consist of two vertical posts 18.5 feet (5.6 m) apart (24 feet (7.3 m) in high school football) rising from a horizontal crossbar, which is mounted on a single central support post that raises the crossbar to a height of 10 feet (3.0 m), resulting in a two-tined fork shape. The central vertical post is offset from the crossbar toward the rear, placing it as far as possible from the field of play; it is also usually padded to minimize collision-related injuries. In 1974, in the effort to create a safer, unimpeded field of play in the end zone, calculated to produce more passing touchdowns, the NFL relocated the goalposts from the goal line to the end line.