Ireland wants to build its base of Test-level players ahead of next year's Rugby World Cup and beyond.
Head coach Andy Farrell said the first game against the Māori All Blacks was huge for the players involved.
"It's everything to these players who are taking to the field tomorrow. It's the biggest game of their lives," he said.
While the tour's emphasis was on the Test series, the two Māori All Blacks games provided an opportunity to build their base and assess how players reacted under the pressure they would face.
Farrell said the team to play the Māori All Blacks were training as a squad of 23 while the remaining players were preparing for the first Test.
"The Test match boys are not training with the subs. We are waiting to see how the Wednesday night game goes and who is going to get picked to take to the field in the 23 for the Test match.
"We picked that on purpose because we want to be adaptable. We want to put ourselves under pressure. I am sure the All Blacks are thinking the same," he said.
Farrell was cautious in assessing the likely impact of the Covid-disruption in the All Blacks' camp due to the loss of David Havili, Jack Goodhue and Will Jordan to Covid.
He said Ireland had one player out with Covid, and there was always a chance more players could be affected.
"This is the way of the world, isn't it? The motto of the tour is being adaptable. When you look at our situation it's not far off what's happening with the All Blacks," he said.
Farrell didn't think the calling-up of former Ireland head coach Joe Schmidt by the All Blacks would have an effect on Saturday's game.
"I am sure Fozzy [All Blacks coach Ian Foster] will be around somewhere. I think Joe is just helping out by being an extra pair of hands. I am sure that Joe is just fitting into the system.
"I mean, what can he bring? He's coming into a system that he probably doesn't know as well. It's not his system.
"I'm sure he is just bringing his one-to-one expertise and advice to the coaches. I am sure they will all try and learn something off him," he said.