Saitama, Japan – Australia dreamed of an Olympic final in men's basketball when they led the United States by 15 points in the second quarter of their last four clash Thursday – but the mighty favorites stormed back to triumph in a dominant 97-78 win.

The US have won the last three Olympic golds, and six of the last seven.

But warm-up losses – including one to Australia – raised eyebrows ahead of the Tokyo Games.

A group stage defeat to France confirmed the team, led by superstar Kevin Durant though without Lebron James, remained vulnerable when competitive action started.

Dante Exum's basket, with a free throw on top, extended Australia's lead to 41-26 midway through the second period. At which point the US said enough.

The advantage was cut to three by halfway and a crushing 32-10 third quarter effectively settled the contest in favor of the US.

Team USA will now meet France or Slovenia in Saturday's final.

Australia will attempt to win a first men's basketball medal, after four previous fourth place finishes, against the loser of the other semi-final.

Durant led the scoring with 23 points, strongly backed up by team-mate Devin Booker, who added 20.

After his high shooting performance, Durant became the first US men's basketball athlete to pass the 400 point mark in the Olympics, USA Basketball announced on Twitter.