Striker Kyah Simon has been ruled out for 12 months with a serious knee injury, in a massive blow for the Matildas and her new W-League club Western Sydney.
Football Federation Australia on Tuesday confirmed Simon suffered a torn anterior cruciate ligament in her right knee and will be out of the game for a year.
Simon, who was an integral part of the Matilda's 2011 World Cup campaign, sustained the injury just seconds after entering the field as a second-half substitute in Australia's 4-0 loss to the world No.1 US side in San Antonio on Sunday (Monday AEDT).
"It's obviously a disappointing setback," Simon said.
"My main focus for the next 12 months is my rehab, doing as much as I can within the restraints and returning for the W-League in 2014 and the World Cup in the 2015."
The Matildas will next face China in two friendlies in Wollongong on November 24 and Sydney on November 27, with coach Hesterine De Reus saying Simon's injury was "a big loss for the team."
Simon was one of several major signings by the Wanderers for the upcoming W-League season which commences next month.
The 22-year-old was a key player for reigning W-League champions Sydney FC last season, named player of the match in last year's grand final win.
Simon is also one of just four Australians to feature in this year's inaugural season of the National Women's Soccer League in the US, where she played for Boston Breakers.
"I was looking forward to the season ahead in the W-League with a good group of players at Western Sydney Wanderers," Simon said.
"Although I won't be on the park I will still be involved off-field and will be sure to share my support and knowledge throughout the season."