Invented in 1977, and originally called murderball, wheelchair rugby made its Paralympic debut at Sydney 2000. The sport is played by mixed teams of men and women. Players score goals by carrying a round ball across the opposition’s goal line with at least two wheels of their wheelchair on the ground. The field of play is a hardwood court measuring 28m by 15m. There is an 8m goal-line at each end, marked by cones. Teams consist of 12 players, with four allowed on the court at any one time. Players all have impairments affecting their arms and legs, and are classified using a points system measuring functional physical ability. Each individual is scored from 0.5 up to 3.5 – the lower the number the greater the activity limitation. The four players on the court cannot exceed a total of eight points. For each female player on the court, an additional half point is allowed. Defensive positions are usually played by low-point players, while attacking players often have higher points. They can be distinguished easily by their wheelchairs. Offensive wheelchairs are shorter, with small bumpers and rounded wings so they can turn and maneuver through tight spaces. Defensive wheelchairs are longer and have a wide bumper in front designed to strike and hold opposing wheelchairs. Games consist of four 8-minute quarters. If the game is tied at the end of regulation play, three-minute over time periods are played. Teams have 12 seconds to move the ball from their court into the opposition’s half, and 40 seconds to score a goal or they must hand over possession. The player in possession must bounce or pass the ball within 10 seconds of receiving it. To pass the ball, players may throw it, roll it, bat it, or bounce it. Kicking the ball is not permitted. This is a full contact sport and clashes between wheelchairs are very much part of the game. Hitting and blocking is used by both defensive and offensive teams, to stop the ball carrier or to create openings for a goal. However, dangerous contact, such as hitting a player from behind, is generally not permitted. Wheelchair rugby is a fast and furious contact sport that makes for spectacular viewing.