This penultimate Olympic qualification tournament, which starts tomorrow and concludes on Sunday (May 30), involves the host teams and others based either on their finishing positions at the International Basketball Federation (FIBA) 3x3 World Cup 2019 or on the fact that they are the highest-ranked teams in the FIBA 3x3 rankings not yet qualified.

Serbia, ROC and China have already qualified for the Games as the top three men's teams in the FIBA 3x3 ranking along with Olympic host Japan.

Women's qualifiers will join the ROC, China, Mongolia and Romania, who have already qualified as the top four teams in the FIBA 3x3 rankings as of November 1 2019.

In women's 3x3 basketball, the host nation has not qualified automatically so Japan will be playing in Graz.

The last opportunity to qualify for the Tokyo 2020 will take place at the FIBA 3x3 Universality Olympic Qualifying Tournament in Debrecen in Hungary from June 4 to 6.

That will finally determine the full extent of the 16 teams - eight men’s, eight women’s - that will make Olympic history from July 24 to 28, and offer one berth for each gender.

The short timeframe of 10 minutes and the 21-point target as two teams of three players face off on half a basketball court means upsets can often happen, and FIBA statistics show that on average one in four games is decided by a single basket.

But those expected to do best in the men’s event are Latvia, who can call upon professional F3x3 World Tour players Karlis Lasmanis and Nauris Miezis, and the United States, who will be led by 2019 World Cup Most Valuable Player Robbie Hummel and can also field Kareem Maddox, Dominique Jones and Canyon Barry.

In the women's event top billing is likely to go to world number one-ranked France, headlined by the world's top two players in Laetitia Guapo and Migna Touré.

France won on their return to 3x3 Women's Series action last weekend.

Australia will also be strong challengers, as will 2019 World Cup silver medallists Hungary.

There will be 94 games played in Graz over five days.

Teams are placed in pools of five, with the top two qualifying for the knockout rounds on the final day.

The last six games - semi-finals and third-place games - will be known as the "Olympic Ticket" matches and the winners will all qualify directly to the Tokyo Olympics.

FIBA will be broadcasting live and without geo-restrictions on Twitch, Facebook and YouTube, with the governing body also announcing deals with more than 30 broadcasters in excess than 100 countries worldwide - it says that will deliver the biggest TV coverage in 3x3 history.

The 3x3 discipline was played for the first time in international competition at the 2010 Youth Olympic Games in Singapore and since then has benefited from the launch of a yearly city-based FIBA 3x3 World Tour and competitions for national teams.

It is making a full Olympic debut at Tokyo 2020, and a test event was recently conducted in the Japanese capital.