It was the Kiwis' first win in an Anzac test since 1998, breaking a run of 15 successive losses to the Kangaroos.
Perhaps more importantly, it backed up the success achieved last November, when the Kiwis won the Four Nations, beating the Kangaroos twice in the process.
"This is huge," said Johnson. "It's actually hard to but into words but it means so much. We knew they had players missing last year and we knew most of those players were back. So to come out and perform again was crucial, and it shows the self belief we have in this team."
The result means the Kiwis have now won three successive matches against the Kangaroos, the first such hat-trick of wins since a wondrous spell in 1952 and 1953 when the Australians were defeated four times.
"It's big for New Zealand league," said Johnson. "It has been a long time coming but this group has a lot of belief."
Johnson had a big match, crossing for a typical solo try in the first half and sparking the move that led to Shaun Kenny-Dowall's try on the stroke of half-time. He also made 20 tackles on defence in a committed display.
Meanwhile, fellow Warrior Manu Vatuvei had a match for the ages, scoring two tries (and going extremely close to a third) in a Man of the Match performance. Vatuvei, who has been in the team for more than a decade, was revelling in the result.
"It feels great," said Vatuvei. "We prepared well, worked hard and [that] showed out on the field. Everybody was working for each other, that's our spirit."
- Michael Burgess in Brisbane
