Australia had to come from behind to eke out a gritty 10-point win over Japan at the FIBA Women's Basketball World Cup qualifying tournament in Turkey.

After trailing for much of the contest, the Opals lifted defensively in the final quarter, holding Japan to just four points to seal the game 81-71 in Istanbul on Thursday.

Captain Sami Whitcomb led the Opals with 17 points, knocking down four from the arc, while Ezi Magbegor added 14 points.

Alanna Smith shone in defence for Australia with 12 points, nine rebounds and three blocks, helping the Opals dominate the glass with 51 rebounds total for the game.

Zitina Aokuso provided a spark off the bench with 10 points and seven rebounds, while Steph Talbot finished with eight rebounds and two key three-pointers during the Opals' late surge.

Whitcomb said the team's resilience proved decisive.

"We really liked the grit that we showed in that second half, in particular that fourth quarter," she said.

"Japan's a great team and they made a really great run after I thought we started the game pretty well.

"Things weren't going our way. We'd make a run and then they'd hit a couple of tough threes, but I thought we did a great job of hanging in there and fighting defensively.

"Talbs (Steph Talbot) hit a couple of really huge threes and that brought us back in."

Opals coach Sandy Brondello said the contest provided an important test for the Australians against a determined Japanese side.

"It was a great hit-out for us," Brondello said.

"I explained to them that Japan were going to have some urgency because they need to win. They're trying to qualify and do something big here.

"You're not always going to have a great first half at a tournament, but we found some grit in that third quarter, and the group we had on the floor were elite defensively. Our defence created our offence, and that is our identity."

The Opals now enjoy a rest day before returning to the court to face Hungary on Saturday at 10.30pm (AEDT).

Australia have already qualified for the World Cup after winning the 2025 FIBA Asia Cup championship.