Jackson top-scored at the Athens Olympic Games in 2004
World champions Australia and defending Olympic champions the US both eased to victory in their opening group matches of the women's basketball tournament.
Lauren Jackson scored 18 points and 10 rebounds as Australia overcame Belarus 83-64 to go joint top of group A.
The US, champions at the last three Games, took a share of the group B lead by beating the Czech Republic 97-57.
South Korea and Russia won their first group A games and New Zealand and China were victorious in group B.
Australia, who have lost the last two Olympic finals to the Americans, are slim favourites for the title in Beijing.
A 71-67 loss to the US in the FIBA Diamond Ball tournament in Hainang last week - the first match between the teams since the Athens 2004 final - highlighted how close the competition is likely to be.
After shooting just 38% in the first half, Jackson lifted the Australians in the third quarter with seven unanswered points.
The Opals were tentative in the opening stages, but built a 19-12 lead at quarter time and expanded that to 44-28 at the half.
Defence was the key to our win tonight - we forced the Czech Republic into 27 turnovers and we took full advantage
USA centre Candace Parker
"Our girls were challenged by the fact we have never played Belarus," said Australia coach Jan Stirling.
"For us it was a significant game, and I think our recent loss in the Diamond Ball against the USA helped prepare us for today.
"We're just chipping away at a number of things - we've got quite a few things to work on, but I thought we executed pretty well."
The US were slow to get going against the Czechs but Diana Taurasi and Tina Thompson soon sparked them into life.
Taurasi finished with 17 points and Thompson seven in front of an onlooking US President George W Bush.
Trailing 13-2 nearly five minutes into the game, Thompson and Taurasi combined to score all the points in an 8-0 run.
"Defence was the key to our win tonight," said USA centre Candace Parker after her side scored 12 points off turnovers. "We forced the Czech Republic into 27 turnovers and we took full advantage."
"We were cautious at the start because this was our opening game of the Olympics but then we picked up our game and now we look forward to taking on hosts China."
China, who face the US on Monday, held off Spain 67-64 with Bian Lan scoring 15 points and 12 rebounds and captain Miao Lijie and Chen Nana adding 12 points apiece.
The Chinese dominated until the last quarter, holding 13-point margins at stages of the second and third quarters until Spain came back, led by Alba Torrens with 18 points.
Beon Yeon-ha and Choi You-nah each scored 19 points to help South Korea edge Brazil 68-62 in overtime.
After overcoming a six-point deficit in the closing stages of regulation, time South Korea went on a 11-2 run to start the extra period and never looked back.
Brazil had a chance to win the game at the death but Micaela Jacinto missed a 15-foot shot from the corner that bounced off the rim twice before falling out.
South Korea next play Russia, who came through 62-57 against Latvia in the opening day's late game.
Angela Marino scored 19 points and Kate McMeeken-Ruscoe hit two late three-pointers to help New Zealand scrape past Mali 76-72.