"We've had a solid couple of days together, and all the lads have really impressed me with their enthusiasm and energy,'' Kearney said in a statement.
"We're under no illusions about the task ahead of us - the Aussies are a world champion side and we will have to be on top of our game to match them.
"But we have confidence in our talent, and there's definitely a spirit in this group that augurs well for this game and beyond.''
Kearney's call-up of John revives memories of Olsen Filipaina's legendary deeds for New Zealand.
The former Kiwi pivot was selected out of Sydney's reserve grade competition in 1983 and 1985 to inspire New Zealand to upset wins.
New Zealand: Peta Hiku, Roger Tuivasa-Sheck, Dean Whare, Gerard Beale, Jason Nightingale, Isaac John, Shaun Johnson, Jesse Bromwich, Ben Henry, Sam Moa, Simon Mannering (capt), Kevin Proctor, Adam Blair, Siliva Havili, Martin Taupau, Greg Eastwood, Tohu Harris, Kenny Bromwich (18th man).
-AAP