There are two changes in the front row as prop Jack McGrath and hooker Sean Cronin come in, with Niall Scannell and Cian Healy dropping to the bench.
Ulster winger Jacob Stockdale returns to the starting line-up, after he was a shock omission from Melbourne, as do Leinster No8 Jack Conan and former Chiefs inside centre Bundee Aki, now at Connacht.
They replace injured trio Andrew Conway, Garry Ringrose and Dan Leavy.
Schmidt is also forced into three positional changes, with captain Peter O’Mahony moving to open-side flanker, CJ Stander shifting to blindside to accommodate Conan, and Robbie Henshaw starting at outside centre.
The Ireland squad visited @TadhgKennelly & the @sydneyswans today and had a bit of fun when Tadhg met Mícheál Ó Muircheartaigh (AKA Ireland physio Colm Fuller) Check it out on youtube https://t.co/lyfti5s7Z2— Irish Rugby (@IrishRugby) June 20, 2018
Stockdale, McGrath and Aki were in the team for the opening Test, but it will be a first start of the series for Cronin and Conan.
There were further changes among the Ireland reserves, with John Cooney and Joey Carbery replaced by Kieran Marmion and Ross Byrne – the only member of the Irish squad not to have been involved in a matchday squad on the tour so far.
Ireland Team v Australia, Allianz Stadium, Sydney, Saturday, June 23, 14:05 UAE time
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