All Blacks defence coach Scott McLeod said he hadn't been surprised with how Japan was playing because he had worked with their coaches Jamie Joseph and Tony Brown at the Highlanders, and the way they wanted to play the game was familiar.
"They've got a high skill level ,and they put the ball into space really well very quickly, and if they get their space with their skill set, they can be very dangerous.
"They've got some power players and fast players and the other balance from that which is familiar is that if they don't get what they want then they are very happy to kick the ball and back their defence and then pressure and try to get turnovers."
Japan got better each week in their three games against Australia A and reached a level the coaches would be happy with.
"They are talking about beating the All Blacks with this style of play.
"We have to accept that challenge and with our defence we need to think fast and move fast and not give them any opportunity to play."
Reflecting on how the side's defence had performed during the season, McLeod said they took some lessons from their series loss to Ireland around thinking and moving faster.
They applied those lessons against South Africa and Argentina and used more of the speed of the game against Australia.
"Where we finished up with them, we were happy with our defensive efforts there."
During the season, there were moments when players switched off, and they worked hard to address that. But with players having had time off and some not playing, they needed to get back to the top level quickly, especially in dealing with the speed of the game Japan employs.
"Our movements will be test and that's what we're working on hard this week."
It was another different style of rugby, as it would be when they play Wales, Scotland and England, and that put the emphasis on being able to adapt.
"We've played a lot of different styles of rugby this year and we feel the quicker we can adapt and the quicker we can see the cues we are looking for, the quicker we can execute the better."