Alaalatoa to captain Wallabies in new-look side for Georgia
Schmidt appointed Liam Wright as the first skipper of his tenure for their win against Wales in Sydney this month, but he was injured and James Slipper took over for the second Test in Melbourne.
But neither were in the 23 for Saturday's clash in Sydney against the Georgians, who are fresh off a narrow win against Japan in Sendai.
Schmidt instead opted to continue experimenting for Australia's final match before the Rugby Championship in August, where they will start with back-to-back games against world champions South Africa.
"Georgia have proven to be a very tough team to play as demonstrated by their wins against Italy and Wales in recent years, as well as their victory last week in Japan," said Schmidt.
"They have added some very exciting backs to their traditional forward strength and challenge opponents across the park."
The 21-year-old Lancaster will join the backs alongside Filipo Daugunu and Tom Wright.
Isaac Kailea and Billy Pollard both earn their first starts in the front row with Alaalatoa while Nick Frost returns for the first time in 2024, combining with Angus Blyth in the second row.
Harry Wilson will play his first Test since 2022 at No.8 with Fraser McReight and Rob Valetini retained at openside and blindside flanker respectively.
Tate McDermott and Ben Donaldson will combine in the halves, replacing Jake Gordon and Noah Lolesio, who started both Tests against Wales.
Centre Len Ikitau returns from injury partnering in the midfield with Hunter Paisami.
Alex Hodgman has the opportunity to join rare company as just the fourth man to represent both New Zealand and Australia in Test rugby, named as the substitute loosehead prop.
Australia (15-1):
Tom Wright; Filipo Daugunu, Len Ikitau, Hunter Paisami, Darby Lancaster; Ben Donaldson, Tate McDermott; Harry Wilson, Fraser McReight, Rob Valetini; Angus Blyth, Nick Frost; Allan Alaalatoa (captain), Billy Pollard, Isaac Kailea
Replacements: Josh Nasser, Alex Hodgman, Zane Nonggorr, Tom Hooper, Jeremy Williams, Nic White, Noah Lolesio, Andrew Kellaway