Loosehead prop Karl Tu'inukuafe and hooker Asafo Aumua will start with George Bower dropping to the reserves and Aumua getting his first start with Codie Taylor out and Samisoni Taukei'aho coming off the bench again.
Foster said the selection reflected the five Tests in five weeks programme and the different nature of preparation this week with their flight to Brisbane in midweek and then a six-day turnaround next week for the second Test.
While last week's captain Ardie Savea and hooker Codie Taylor were clear to play, the selectors erred on the side of caution in not choosing them.
With some variations expected from Argentina's scrum loosehead prop Karl Tu'inukuafe had been given a start this week.
It will be hooker Asafo Aumua's first start for the All Blacks, and Foster said he was ready.
"He had an unfortunate July series through injury when he wasn't able to get on the park. We said we wanted to get him back into NPC to get a few runs on the board, and we got one, but we couldn't get any more.
"He's ready to go last week and disappointed he wasn't in the group last week. So this is his time, and I'm excited about how he's going.
"He might take a little while to get used to it. It's not easy in your first Test start and you're playing against a team that probably scrums differently to what he'll be used to and there will be a lot of pressure at lineout time. He's a quality young man and it will be a great experience for him," he said.
Argentina would be looking to repeat their first success over the All Blacks in Australia last year, and Foster expected another tough contest.
Argentina was a well-organised team defensively and had some strengths they liked to stick to.
"They've clearly had a pretty tough road to get here with going to Europe and then having to go to South Africa and then coming into the same soft quarantine that we've been in. They didn't play a game last week so they'll be well rested and passionate about this game," he said.
Knowing the approach of the Argentinians to the breakdown through their loose forwards and locks, their ability to hold players up in the tackle had been an attraction in playing Luke Jacobson at No8.
"Luke's ability with his footwork, to get weak shoulder and to win those collisions he generally does it in a slightly different way to some other loose forwards.
"He's not just a big power runner, he's got an agility, fend and offload that goes with that so getting creative around that space and defensively, he has never been shy in that space. In the last couple of years he's been one of the more dominant tacklers we have in New Zealand rugby and so we're excited about seeing that space," he said.
The competition was hot in the three-quarters where all the contenders were showing good form.
Rieko Ioane is on the bench with the ability to cover centre and wing. Sevu Reece, who Foster said was one of the form backs in the Steinlager Series, had been given a rest last week and would be ready to go, and George Bridge was back into his best form, so it was important for him to have a starting opportunity, he said.
"He's fast, he's sharp, he's contributing. We've added him to our strategy group because he's got a sharp brain in the back three. He's in a good place. He's got internal drivers that are pretty powerful, he just wants to go out there and play well and I'm confident he's where he needs to be to play at Test level now," he said.
It was a big challenge for prop Joe Moody to return off the bench, but Foster said he was ready. His return to play had been outstanding, and while they wanted him to come back after games for Canterbury, that wasn't possible, so they felt having him in Australia was the wisest thing to do, and that decision had paid off.