Australia will be without Dante Exum at this year's Rio Olympics.
The Utah Jazz on Sunday said their NBA point guard would not participate in next month's selection camp or the Games to instead focus on training and recovery from a knee reconstruction in September last year.
It's a massive blow for the Boomers and their hunt for a maiden Games medal, with likely No.1 NBA Draft pick Ben Simmons already ruling himself out and Golden State Warriors star Andrew Bogut in doubt with knee bruising.
Exum injured the anterior cruciate ligament in his left knee while playing for Australia in a game against Slovenia last August in preparation for the Oceania Olympic qualifiers.
He had surgery a month later, forcing him to miss the entire 2015-16 NBA season.
He only returned to full-contact activities in recent weeks.
"At this stage the most important thing for me right now is to continue training," Exum said in a statement.
"It's been great to be back on the court competing, and I'm really motivated to help the Jazz have a successful season this year.
"My support and best wishes will be with the Boomers this summer, and I look forward to future opportunities to represent my home country."
Despite Exum's withdrawal, Boomers coach Andrej Lemanis has a number of guard options behind Patty Mills and Matthew Dellavedova.
Among them are NBL stars Kevin Lisch, Damian Martin, Adam Gibson and Cameron Gliddon, who are all in the current 17-man squad.
Lemanis will cut that back to 12 during next month's camp in Melbourne, between July 5 and 14 - which includes two games against the PAC 12 college all-stars at Hisense Arena.