Aug. 15, 2008, 12:11 p.m. (ET)

BEIJING (AP ) - Lauren Jackson scored 30 points and Australia remained unbeaten with a 96-73 victory against Latvia on Friday.

Latvia provided the stiffest challenge so far for the Opals, playing them tough for the first half before Australia went on a 21-8 run to start the third quarter. Penny Taylor scored seven straight points during the spurt as Australia extended a three-point lead to 16. Jackson hit two 3-pointers to close out the quarter and give the Opals a 76-56 lead.

"She was really unbelievable," Taylor said of her teammate. "She lifted us when we were struggling offensively."

The Latvians would get no closer than 16 in the fourth quarter.

Suzy Batkovic added 18 points and Taylor had 11 points and 11 rebounds for Australia (4-0), which has a showdown with Russia (4-0) on Sunday for the top spot in the pool. The Russians also struggled in their 74-64 victory against winless Brazil.

Trailing by two after three quarters, Russia opened the fourth with a 17-6 run to take a 71-62 lead with 2:05 left in the game. Brazil would get no closer than seven the rest of the way.

"We've been struggling, but have been finding ways to win," said Svetlana Abrosimova, who scored six points in the victory.

Tatiana Shchegoleva had 14 points to lead Russia.

Adriana Pinto led Brazil (0-4) with 21 points, hitting five 3-pointers.

Against Australia, Ieva Tare scored 14 points and Anete Jekabsone-Zogota added 13 for Latvia (1-3).

Jackson took over in the second quarter, scoring 13 of her points. Latvia scored the first seven of the period to take a 25-19 lead on Gunta Basko's 3-pointer. Jackson then went to work, hitting three 3-pointers and a breakaway layup to give the Opals a 41-38 lead at the break.

"We were down and I knew I had to start being more aggressive," Jackson said. "I don't know what it was, but we weren't playing well in the first half."

Basko had banked in a 3-pointer at the top of the key at the end of the first quarter to pull Latvia within one.

In other games Friday, the Czech Republic beat New Zealand 90-59, Belarus topped South Korea 63-53, and China routed Mali 69-48.

The Czech Republic (2-2) clinched a berth in the quarterfinals with its win. They jumped on New Zealand (1-3) in the first quarter taking a 26-12 lead and extended the advantage to 65-38 after three periods. Hana Machova scored 23 points and Eva Viteckova added 21 for the Czech's. Angela Marino led New Zealand with 22.

Yelena Luchechanka scored 10 points and had 14 rebounds for Belarus (2-2), which earned a spot in the quarterfinals. South Korea (1-3) will face Latvia on Sunday with the winner earning the final berth in the next round.

Miao Lijie scored 17 of her 25 points in the first half as China (3-1) ran out to a 17-point halftime lead and cruised to the victory. Miao was hitting shots from all over, going 5-for-8 from behind the arc. With a win over the Czech Republic on Sunday the host country would clinch the second seed in their pool. Djene Diawara scored 11 points to lead winless Mali (0-4).