Johnny Sexton has questioned the "strange" negativity around Ireland's World Cup campaign, insisting Joe Schmidt's men are ready to peak for the All Blacks.
British and Irish Lions out-half Sexton insisted Ireland always knew Japan's quality ahead of their 19-12 Pool A loss to the tournament hosts.
Japan beat Scotland 28-21 on Sunday to tee up a quarter-final clash with South Africa, handing Ireland a last-eight battle with back-to-back world champions New Zealand in Tokyo on Saturday.
Leinster star Sexton hopes Ireland have already shaken their typical World Cup quarter-final performance "out of our system" with that surprise loss to Japan - and now called on his side to produce one of their best-ever performances against the All Blacks.
"We've been building pretty well apart from that poor 60 minutes against Japan; everything else has pretty much gone to plan," said Sexton.
"There's been some negativity around us and we'd feel that's been pretty strange.
"But we're really confident in how we're building. We'd like to be playing a bit better in some regards at times, but hopefully we can put that performance out there on Saturday.
"We're very self-critical in terms of our performances and obviously after the Japan game we would have liked to have done things differently.
"But we knew how good a team Japan were, so we always knew that would happen if we didn't play well, and it did happen.
"So I think looking at the Scotland game last night, Japan were excellent again. They have been through the whole tournament.
"They were clinical with the ball, every time Scotland gave them the ball they seemed to hold it for 20 or 30 phases.
"It was pretty impressive, so I'm sure they will go on and really worry South Africa."
Ireland's failure to launch past a World Cup quarter-final has become a millstone around the team's neck.
Now Kiwi boss Schmidt has the chance for another history-making achievement, should he guide Ireland past his homeland and into a maiden World Cup semi-final.
Ireland lost 22-10 to Wales in the 2011 quarter-finals, before Schmidt's injury-ravaged men were thumped 43-20 by Argentina in Cardiff four years ago.
Sexton hopes Ireland's defeat to Japan will prove their main aberration for this competition then, especially as Schmidt's side this time approach the knockout phases with a clean bill of health.
In 2015, Ireland faced Argentina without Sexton, captain Paul O'Connell, back-row stalwarts Sean O'Brien and Peter O'Mahony - and further backline talents Jared Payne and Tommy Bowe.
Bundee Aki faces a disciplinary hearing on Monday night and could be ruled out for the remainder of the tournament through suspension after his red card against Samoa.
I'm hoping that having lost a pool game that we've got that quarter-final performance out of our system that we've had in other tournaments
But beyond that Ireland have everyone battling for selection, leaving Sexton hopeful of yet more history this weekend.
"I'm hoping that having lost a pool game that we've got that quarter-final performance out of our system that we've had in other tournaments," said Sexton.
"The way we played against Japan was probably very similar to the way we played against Wales and Argentina in the last two tournaments.
"The difference now is we're not favourites going into this quarter-final whereas we were in the last two.
"So we're building nicely, we haven't hit our best performance yet and we need to get close to that to get the right result on Saturday.
"It makes a big difference having everyone fit, even just for the quality of training.
"I remember that Argentina week. We had guys like (analyst) Vinny (Hammond) running against us, and it wasn't the best quality opposition, physically and personally!
"But this week we have everyone fit, we've two good sides for training, so we can make the most of it."
Follow Ireland v New Zealand on Saturday 19 October (kick-off 11.15am) via the live blog on RTÉ.ie/Sport and the News Now App, watch live on RTÉ2 or listen to live match commentary on RTÉ Radio 1.