A stunning late rally from the Matildas came to nought when the United States scored in injury time for a 3-2 victory in a rain-soaked women's soccer international in Cary, North Carolina.
The Australians had hit back from 2-0 down with two goals in the final six minutes from Kate Gill and Cheryl Salisbury to level, as they sought their first win over the Americans in 19 meetings.
Carli Lloyd bagged the winner for the home team in the first minute of injury time when she headed home a punched clearance from Australian 'keeper Lydia Williams.
The Matildas were using the friendly international against the reigning Olympic champions to tune up for the Asian Cup in Vietnam from May 28 to June 8, having failed to qualify for the Beijing Olympics.
Heather Garriock assisted on Gill's goal to highlight her 100th international appearance, which made the 25-year-old midfielder the youngest Australian player to reach 100 caps.
Salisbury gave Australia real hope when she tied the scores in the 88th minute, following her deflected penalty kick with a header that got past American `keeper Hope Solo.
But the Americans overcame some soggy conditions, a 53-minute weather delay - and Australia's frantic comeback - to successfully kick off the three-city friendly tour that precedes Beijing.
Natasha Kai and Abby Wambach had also scored for the Americans, who were playing on home soil for the first time this year as new coach Kia Sundhage fine tunes their attack for this summer's Olympics.
The field was drenched after heavy rain began falling about an hour before kickoff.
Lightning and thunder claps pushed the start time back nearly an hour, the players spent much of the first half contending with puddles near Williams' goal and much of the second half was played in a steady downpour.
The Americans controlled play early, with Lloyd and Wambach peppering Williams. Kai put the US up 1-0 in the 35th minute when she bounced a shot off the inside of the right post and past the `keeper for her seventh goal of the year.
Another scoring chance was thwarted two minutes later when Kai was looking at a sure-thing breakaway chance when she tried to manoeuvre around Salisbury, but the Matildas captain dragged her down and was issued a yellow card.
Wambach made it a two-goal game in the 49th minute by scoring in her fifth straight game. She took a cross from Amy Rodriguez and headed the ball past Williams for her 93rd career goal, moving her closer to becoming the eighth player to reach the century mark in international play.
The teams meet again on Saturday in Birmingham, Alabama.