If Australia and Japan are to beat the All Blacks in the coming weeks when they meet in Yokohama and Tokyo, respectively, they will have to defeat a side who, by their own admission, can "still get better and smoother in some areas."

New Zealand may be the two-time defending and three-time World Cup champions but, as assistant coach Ian Foster said Tuesday, "I don't think we're ever pleased. We're a grumpy bunch in some ways."

(Rieko Ioane, left, and Beauden Barrett)

They are also a side that never looks beyond the next game, meaning all their thoughts for the moment are on Australia, who they face at Nissan Stadium on Saturday.

"As much as we are loving being here we haven't thought much about (Japan) in terms of the game coming up. That's just us," Foster said.

"We're probably not smart enough to think two games in advance. We know how much Australian games take out of us. For us it's a massive opportunity to play well away from home and to get a little bit of a simulation of what is to come next year (at Rugby World Cup 2019)."

"We'll deal with the Japan challenge when it comes, but we've seen enough from them to know it will be a significant challenge."

That desire to take one game at a time will, Foster said, be equally important next year in Japan when the All Blacks look to once again get their hands on the Webb Ellis Cup.

"What we are doing here and now is great preparation. It's about learning to concentrate on one challenge in front of us. We know that if you don't do the one at a time well enough you'll get bowled," he said using a cricket analogy that some of the local reporters understood following countless references to the game from ex-Japan coach Eddie Jones.

(Ian Foster)

The All Blacks have not lost two successive games since 2011 -- a run of 99 tests -- so the chances they fall twice while in Japan, even with a weaker side against the Brave Blossoms, is slim to say the least.

After the test against Australia, 22 of the 32 players in the main squad will head to Europe with an additional 19 players flying in to prepare for the game against the Brave Blossoms.

The additional players, 10 of whom are uncapped at test level, will then return home while the main squad members travel on to London to rejoin their teammates ahead of matches against England, Ireland and Italy.

Those getting to don the famous black jersey for the first time will be joining an elite group that does all it can to remain humble despite their success.

"It's no secret," flyhalf Beauden Barrett said of New Zealand's success. "You have to work really hard, you have to have high standards and live those standards and be accountable. We have a great culture and get the balance right. We work hard but really enjoy ourselves...You can't take for granted that we are going to keep on winning."

One player who has bought into that culture since making his debut in 2016 against Italy is Rieko Ioane.

The wing's father Eddie played here for Ricoh and Ioane's older brother Akira was born in Tokyo.

"There's a bit of history with my family with Japan," the 21-year-old said, adding that it was something of a career highlight to be in line to play two tests here.

"But as great a city as Tokyo is, we've still got a job to do. We've got a huge game coming up on Saturday and all the boys are focusing on the Aussies."

Saturday's Bledisloe Cup game at Nissan Stadium kicks off at 3 p.m., while the All Blacks versus Brave Blossoms match on Nov. 3 at Tokyo's Ajinomoto Stadium gets underway at 2:45 p.m.

Japan warm up for their clash with the All Blacks with a game on Friday evening at Osaka's Hanazono Stadium against a World XV, with kickoff set for 7 p.m.