There is an underwater version of rugby. It is a contact sport between 2 teams of 6 competing underwater in a pool to score goals while freediving.
Underwater rugby (UWR) is an underwater team sport. During a match, two teams try to score a negatively buoyant ball (filled with saltwater) into the opponents’ goal at the bottom of a swimming pool. It originated from within the physical fitness training regime existing in German diving clubs during the early 1960s and has little in common with rugby football except for the name. It was recognized by the Confédération Mondiale des Activités Subaquatiques (CMAS) in 1978 and was first played as a world championship in 1980.
It is played underwater in a pool with a depth of 3.5m to 5m and goals (heavy metal buckets with a diameter of about 40 cm) at the bottom of the pool. Two teams (blue and white), each with six players (plus six substitutes), try to score a goal by sending the slightly negatively buoyant ball (filled with saltwater) into the opponents’ goal. It is a fast and exhausting game; therefore, the subs replace their players on the fly.
The ball may be passed in any direction but must not leave the water. It "flies" about 2m or 3m before water resistance stops it. This makes good tactics and good (three-dimensional) positioning essential. The players need all sorts of different abilities: Strength, speed, agility or good team play are all similarly important.