Playmakers Aaron Smith and Richie Mo'unga say the All Blacks have taken "massive steps" from their troubles of last year and are ready to challenge for the Rugby World Cup.

The pair showcased their class when emerging from the bench to help a weakened New Zealand come back from 17-3 down to edge Australia 23-20 in Dunedin on Saturday.

Scrum-half Smith provided direction while fly-half Mo'unga landed a 79th-minute penalty to ensure the All Blacks remained unbeaten this year and upbeat about their prospects five weeks out from the World Cup in France.

The pair loom as key figures at the global showpiece, which could see their final appearances in Test rugby, with both having signed to play for Japanese clubs next season.

Smith was heartened by the All Blacks' form during an imperious run through the Rugby Championship, followed by Saturday's fighting win from a new-look starting side featuring 12 changes.

The 34-year-old highlighted the progress made from last year, when they suffered an uncharacteristic four defeats and struggled for cohesion.

"I think we've taken some massive steps from 2022. I'm actually proud of how far we've come this year," Smith said.

"I'm really excited about the future and what this year holds and where our team's at. 

"We just played an amazing Test, blooded some more new boys into our brotherhood. When we got our game plan and our structure going, we were able to dictate terms."

A 118-Test veteran, Smith said it was emotional to play a final Test in New Zealand in front of his home supporters in Dunedin, particularly when leading the pre-game haka.

However, the 34-year-old said he couldn't afford to be distracted as he drove his forward pack to be more intense, something he says they'll need to be in France.

"That was the clear message at half-time: use our maul, use our scrum, build pressure," he said.

"It wasn't pretty but in the end we won. A scrum penalty to win the game, that shows it's the way forward, using our forwards to create opportunities."

Mo'unga said his confidence was buoyed by the All Blacks' superior off-field culture this year.

"We're in a really good place. Even if we had lost this game, I would still be saying the same thing," he said.

"I'm really happy with the little changes we've made as a team, not just the performances on a Saturday but what I see on a Monday to Friday."

New Zealand's World Cup squad will be announced on Monday.

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