Of the four top sides, only the United States, seeking a record-extending eighth triumph, got off to a winning start.

The US who, for the first time since 2005, are not defending this title, earned a 79-56 win in their Group C opener against Australia.

But there was a shock for the hosts, Thailand, as they were beaten in Group A, losing 66-39 to Mozambique, for whom Reka Dombai scored 16 points in what was a memorable debut in this event for the African team.

Further shocks occurred as two other top seeds, Germany and China, lost their first matches.

Germany were beaten 74-67 by Japan in Group D, while China were sunk 64-52 by Belgium in Group B.

Latvia earned a narrow 65-54 win over Canada in the first Group A match.

The second Group C match saw Hungary beat South Korea 92-68.

Spain made a strong opening statement in Group D as they gave Colombia a debut to forget, winning 75-38.

In Group B, Argentina edged past a Mali team inspired by their men’s achievement in reaching the recent men’s under-19 final, 55-52.

The 2017 champions, Russia, are not at the championships having failed to make the cut at last year's FIBA Under-18 Women's European Championship.

This is the 13th edition of the FIBA Under-19 Women's World Cup and the second time that Bangkok has played host.

The city also did so back in 2009, when Thailand lost all five of their matches to finish in last place.

Group phase action is due to take place until July 23, with each team playing against all other sides in their section once.

All teams will advance to the final phase, with Group A crossing with Group B and Group C crossing with Group D in the round of 16 on July 24.

The final phase of the event is also scheduled to be held in Bangkok, with the new world champions being crowned on July 28.

Matches are being played at the Thai-Japan Youth Arena I and II.