Australia broke its own world record in the women's 4x100-meter freestyle relay Saturday to capture the country's first gold in swimming at the Tokyo Olympics.
The quartet of Bronte Campbell, Meg Harris, Emma McKeon and Cate Campbell finished in a time of 3:29.69, which was close to four-hundredths of a second better than Australia's previous world record of 3:30.05.
The United States benefited from a strong third leg out of Natalie Hinds to set up anchor Simone Manuel for a medal-clinching lap.
Manuel finished third, right behind Canada's Penny Oleksiak, to earn the Americans' sixth medal in the pool on Saturday night.
1. Australia (Bronte Campbell, Meg Harris, Emma McKeon, Cate Campbell): 3:29.69
2. Canada (Kayla Sanchez, Maggie McNeil, Rebecca Smith, Penny Oleksiak): 3:32.78
3. United States (Erika Brown, Abbey Weitzeil, Natalie Hinds, Simone Manuel): 3:32.81
4. Netherlands (Kim Busch, Ranomi Kromowidjojo, Kira Toussaint, Femke Heemskerk): 3:33.70
5. Great Britain (Anna Hopkin, Abbie Wood, Lucy Hope, Freya Anderson): 3:33.96
6. Sweden (Sarah Sjostrom, Michelle Coleman, Louise Hansson, Sophie Hansson): 3:34.69
7. China (Yujie Cheng, Menghui Zhu, Yanhan Ai, Qingfeng Wu): 3:34.76
8. Denmark (Pernille Blume, Signe Bro, Julie Jensen, Jeanette Ottesen): 3:35.70
Australia started to pull away on its world-record pace during the third leg.
Emma McKeon turned in a 51.35-second split in the third 100-meter leg of the event. That was the only lap of the competition to be under 52 seconds.
McKeon's fast turn in the pool set the stage for Cate Campbell to pull away during the fourth and final leg.
Campbell swam her 100-meter leg in 52.24 seconds to cruise to the gold medal and the world record. Canada and the United States finished more than three seconds back of the Aussies.
The 4x100 relay gold was the first earned by the Australians at the Tokyo Games. Earlier in the swimming program, Jack McLoughlin took silver in the men's 400-meter freestyle and Brendon Smith captured third in the men's 400-meter individual medley.
Australia previously set the world record in the event in 2018 on the Gold Coast with a time of 3:30.05. The Aussies held the previous Olympic best mark as well. They swam the 4x400 in 3:30.65 five years ago in Brazil.
McKeon, Cate Campbell and her sister Bronte Campbell were all members of the gold-winning team from Rio.
The most drama in the event took place in the battle for second between Oleksiak and Manuel, who shared the gold medal in the women's 100-meter freestyle in Rio.
Oleksiak got the best of Manuel by three-hundredths of a second to give Canada its first medal of the Olympics. Oleksiak's final leg was seven-tenths faster than Manuel's. She got through her 100-meter leg in 52.26 seconds, which was the best Canadian lap time by over a second.
Manuel was one of two American swimmers to go under 53 seconds on their laps. Second leg swimmer Abbey Weitzeil had the best leg of 52.68 seconds.
Weitzeil's fast second lap and third lap from Hinds helped the United States recover from a 54-second opening lap out of Erika Brown.
The U.S. finished Saturday night with six swimming medals, which are the only medals it has won in Tokyo so far.