The pool is deep - so deep that you can't stand up. Players have to tread water for the whole match, which is exhausting. Most use a special leg kick called 'eggbeater' - moving each leg in a different circle - which keeps them up without using their hands. Their hands are busy with the ball.
Each match has four quarters of around 8 minutes. That sounds short until you realise you have been swimming and treading water and throwing and dodging the whole time. Top water polo players are some of the fittest athletes in any sport.
Malta's summer water polo league - between village teams - is one of the most popular sports in the country. Tickets are cheap, families bring picnics, and the matches happen in outdoor pools by the sea. Whole villages come down to cheer.
Children usually start with 'mini polo' in shallow water from about age 8, learning to pass and shoot with one hand while floating. By their teens, the best ones move up to the proper deep pool with their village team. Some Maltese clubs are over 100 years old.