The duo both tasted international action in the RBS 6 Nations as replacements and both impressed after coming off the bench in the closing stages last Saturday.
There's also a change at No.9 for Australia as well as Will Genia replaces Luke Burgess while at inside centre Matt Giteau will look to reignite his magic with fellow playmaker Quade Cooper.
Johnson resisted the temptation to make changes of his own in midfield as Jonny Wilkinson remains on the bench despite rumours that Toby Flood would shift to the No.12 shift to accommodate the return of the 2003 World Cup hero.
And Johnson is adamant that his young duo are ready to be let off the leash against Australia.
He said: "This is a great opportunity for Ben, who has been with us since the middle of the Six Nations - the same for Courtney.
"Ben brings something different to Danny but it is not a reflection on Danny's performance. It is just an opportunity to get Ben on the field.
"It is a tough call on Danny, who has not done anything particularly wrong. Simon Shaw certainly hasn't done anything wrong but Courtney Lawes has really stepped up in the last few weeks since we have been together.
"He is very athletic and gets around the field and is very aggressive.
"There is always a rationale for playing Jonny but we are happy with what we have got with Toby.
"We can't give them that many shots. They are a good team and they will get something on us but we made it too easy for them last week."
Shaw and Care are relegated to the bench where they are joined by the versatile Delon Armitage who takes Mathew Tait's place as a replacement.