"Huge, huge threat,'' Popovich told reporters in Melbourne, Australia, according to The Associated Press. "They are one of the teams that can win the whole thing, without a doubt. I'm not saying that because I'm here. It's just a fact.
"They've been close for several years, and they are hungry. They are talented. They have the toughness and physicality to go with it. I think they are one of the top contenders without a doubt.''
Popovich will get his first of two up-close looks at the Boomers on Thursday when Team USA faces Australia in pre-World Cup action at Melbourne's Marvel Stadium in front of an expected crowd of 50,000. The two sides will square off again in the same setting Saturday.
Due to the World Cup's bracket structure, Australia and the U.S. wouldn't face each other in China until the quarterfinal stage at the earliest; a showdown in the final is possible.
Australia has finished as high as fifth at the tournament on two occasions - 1994 and 1982. The Boomers reached the round of 16 at the last edition in 2014 but lost to Turkey by just one point after conceding a 3-pointer with five seconds left. Australia also matched its best Olympic finish at the 2016 Rio de Janeiro Games, placing fourth after losing to Spain in the bronze-medal game - also by a single point.