Patty Mills led Australia to a 91-83 win over the United States in an exhibition game on Monday but said the 'Boomers' still have a long way to go as they chase a first Olympic men's basketball medal.

The Australians handed Greg Popovic's team their second consecutive warm-up loss ahead of the Tokyo Olympics after the Americans lost to Nigeria on Saturday.

While the United States are hot favourites for gold at the Games, Australia's men are aiming to win an Olympic medal for the first time having previously finished fourth four times.

"We understand, at the start of this campaign, that for us to be able to be really competitive and achieve our goals we need to hang our hat on the defensive end, especially against an athletic team like the United States," Mills told NBC.

"Getting out in transition and making easy lay-ups and dunks, for us to take away that was pretty impressive for our second game.

"But we're not satisfied. We've got a long way to go."

San Antonio Spurs point guard Mills scored 22 points while Joe Ingles hit 17 points but Australia's defence was crucial.

"Winning is one thing, the process is another," said Boomers coach Brian Goorjian.

"We moved the ball better, got better shots and defensively figured things out."

Australia are in Group B at the Olympics alongside Germany, Italy and Nigeria while the United States, who have won the gold medal at six of the last seven Games, are in Group A with Iran, France and the Czech Republic.

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