SHANGHAI, China (AFP) — Basketball’s World Cup launches on Saturday in China with two-time defending champions the United States missing their biggest stars and looking uncharacteristically vulnerable after surrendering their long winning streak.

The chief threat to the LeBron James-deprived Americans looks likely to come from Serbia, but Spain, France, Australia and Greece are all snapping at Team USA’s heels

The chief threat to the LeBron James-deprived Americans looks likely to come from Serbia, but Spain, France, Australia and Greece — led by National Basketball Association (NBA) Most Valuable Player (MVP) Giannis Antetokounmpo — are all snapping at Team USA’s heels.

A total of 32 countries will begin in eight groups of four spread across cities in China, from Shenzhen in the south to the capital Beijing, where the final will be held on 15 September.

Just a few days ago the United States under their respected coach Gregg Popovich were odds-on favorites to make the final and win it for the third time in a row, no matter the opponent.

But last weekend they were stunned 98-94 by Australia in Melbourne, the hosts ending the USA’s run of 78 consecutive wins in major competitions and exhibition games.

Kevin Durant, Kyle Lowry and Klay Thompson are injured.

The Americans bounced back in Australia to beat Canada 84-68 in their last warm-up match before jetting over to China, but their aura of invincibility has dimmed and the players have admitted that they are still getting to know each other.

Myles Turner, a center with the Indiana Pacers, said that his team-mates needed to adapt fast to the international game.

“A lot of times in the NBA you sort of wait until the fourth quarter to turn it on,” said Turner.

“You have to turn it on from the jump here.

“And these teams, everybody wants to beat the USA. We’re the top dog and everybody’s gunning for us night in and night out.”

The US begin their title defense in Shanghai on Sunday when they play the Czech Republic in Group E, which also contains Japan and Turkey, runners-up to the Americans in 2010.

If anyone is going to finally dethrone the US, many fancy it could be Serbia, beaten by the US in the final in 2014. The US also defeated the Serbs in the final at the 2016 Rio Olympics.