Veteran fast bowler Sarah Aley could make her international Twenty20 debut after young quick Lauren Cheatle was ruled out with a back injury.
Aley is one of three new faces in the T20 squad from last week's Test, after Cheatle carried a niggling injury before missing selection for the four-day match.
The injury has helped open the door for 33-year-old Aley, who has been strong performer in domestic cricket for NSW for the best part of a decade but only made her one-day debut this year.
"Lauren has been ruled out with a back injury, she underwent scans yesterday and we are awaiting the results for more detail," national selector Shaun Fleger said.
"Sarah will be hoping to make her T20 debut after being handed her one-day cap during the 50-over World Cup this year."
Nicole Bolton and Tahlia McGrath also drop out of the side that drew last week's Ashes Test, with with offspinning allrounder Molly Strano and medium-pacer Delissa Kimmince brought in.
Australia need to win just one of the three T20s to retain the multi-formatted Ashes, beginning with Friday's clash at North Sydney Oval.
"It's been a long tour for some of the younger players, so the selectors have opted to add some fresh legs to the side, all of which have previous experience at international level," Fleger said.
"We have been really pleased with the way Tahlia has played in the series and as she continues to develop her T20 skills we think she will be an important member of the side.
"It's great to see Delissa back in the side having last played for Australia in 2014, she's a very handy bowler who will also add extra depth to the middle order.
"Molly was impressive with her off-spin bowling during Australia's T20 series against New Zealand earlier this year."
Meanwhile, veteran spinner Kristen Beams is also missing, with selectors sticking with Ashleigh Gardner, Jess Jonassen and Amanda-Jade Wellington.
Beams was Australia's long-term spinner before the series' one-dayers, however she only appeared in one match when Gardner was injured and then missed selection in the Test.
AUSTRALIA'S T20 SQUAD: Sarah Aley, Alex Blackwell, Ashleigh Gardner, Rachael Haynes, (c) Alyssa Healy, Jess Jonassen, Delissa Kimmince, Beth Mooney, Ellyse Perry, Megan Schutt, Molly Strano, Elyse Villani, Amanda-Jade Wellington.