Unlike many sports that come from an Olympic background and go through adaptations, goalball was created exclusively for people with visual disabilities - either blind or partially sighted.
It originated in 1946 in Germany, created by an Austrian, Hanz Lorenzen, and a German, Sepp Reindle, as a form of rehabilitation of veterans of both World Wars.
Nearly 30 years later, during the Heidelberg 1972 Paralympics, the sport took advantage of the Games being held in the country where it was created to make its international debut.
In the next Paralympic Games, held four years later in Toronto, Canada, it officially became a competition, but only for men. Women began participating in 1984, when the Games were co-hosted in New York and Stoke Mandeville, England.
In goalball, two teams of three players throw balls alternately, with the objective of scoring goals against the opponent. Despite the different visual classification of the athletes, they all compete using eyeshades so that no one is disadvantaged.
The game space is the same size as a volleyball court (18m x 9m), and the goals, placed on the end lines of the court, are 9m wide and 1.3m high.
Each half of the court is divided into three areas of 3m x 9m: orientation area, landing area and neutral area. A team may not invade the opponent’s area and can only use its own area to throw the ball - bouncing or rolling - which must touch the ground in the thrower’s own area before entering the opponent’s area.
Players in the defending team may lie on the ground to try to block the entire goal, also within a limited area, and positioning is guided by tactile lines - cords taped to the ground.
In addition to refereeing the match, goalball referees have to control the game, narrating aloud the players’ actions.
All the rules of the sport are determined by the International Blind Sports Federation (IBSA).
The official ball is similar in size to a basketball, but without an internal bladder. It has bells inside and holes on the outside that enhance the sound to orientate the players.
Matches consist of two 12-minute halves, with an interval of three minutes. If a team achieves a 10-goal lead, the match is ended immediately, regardless of the time played.