The Australian women are the reigning Olympic and World champions and world-record holders in the 4x100m freestyle relay.
And they looked stronger than ever before on Tuesday.
Cate Campbell, Bronte Campbell and Emma McKeon all broke 53 seconds in the Australian Olympic Trials 100m freestyle final in Adelaide (52.38, 52.58. 52.80). No American has ever broken 53 seconds.
Brittany Elmslie finished fourth in 53.54 to round out the likely Rio Olympic final quartet.
The top four went a combined 4.72 seconds faster on Tuesday than the top four at the Australian trials in 2012, when the Aussies went on to win the Olympic title by .64 in an Olympic record. They went 1.59 seconds faster than the top four at the 2015 Australian Championships.
“There are four women in the world who are swimming under 53 seconds, and three of them are not just from Australia, we all train in Queensland,” Cate said on Australian TV after the race.
Since the 2012 Olympics, five women in the world have broken 53 seconds -- Swede Sarah Sjostrom, the Netherlands’ Femke Heemskerk (in 2015 most recently) and those three Aussies.
Two of them, the Campbell sisters who took individual 100m free gold and bronze at the 2015 Worlds, came into the Australian trials having dealt with injuries in recent training.
The U.S.’ fastest 100m freestyler since the 2012 Olympics? Simone Manuel‘s 53.25 in 2014.
The Aussies will be heavily favored in the 4x100m free relay on the first night of Olympic competition on Aug. 6, unless the Americans or the Dutch put together vastly faster swims than they’ve ever recorded at their Olympic Trials.
Depending on how trials go, the U.S. 4x100m free relay quartet could include Manuel and Olympic champions Missy Franklin, Katie Ledecky and Natalie Coughlin in a star-studded field.
At the 2015 World Championships, Franklin and Manuel bookended a U.S. quartet that took bronze, 3.13 seconds behind the Aussies.
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