Water polo at the Rio 2016 Olympics: All you need to know

How does it work?

The aim remains to throw the ball into the opponents' goal but a gentle pastime has been replaced by a physical sport, with plenty of unseen gamesmanship beneath the water's surface.

It is played by teams of seven in matches of four eight-minute periods. The competition begins with two groups of six teams, followed by quarter-finals.

Extra time is no longer played - matches go straight to a penalty shootout.

Who are the favourites?

The United States has been the most successful water polo team since the women's event was introduced - and they look unbeatable heading into this summer's Games.

Last year, they became the first team in history to hold the women's Olympic, World Championship, World Cup and World League crowns at the same time.

Serbia's men are considered to be the finest sports team in the country's history and are among the favourites for gold in Rio.

They beat reigning Olympic champions Croatia in the 2015 World Championship final and won a third European title in a row in January.

Who are the British prospects?

Sadly, there are no British teams for water polo fans to cheer on. Team GB did not qualify for Rio 2016 in the men's or women's event.

I didn't know that...

Water polo became the first team sport at the Olympic Games in 1900, but it took another 100 years for the women's competition to make its debut at Sydney 2000.

Previous British medallists

Four (all golds)

Most recent British gold

1920 - men

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