Nonu has recovered from a shoulder injury he suffered in the 18-18 draw with the Wallabies in Sydney and is set to strengthen New Zealand’s line-up.
“We’re sure [he's fit], but we’re waiting to see because there is a whole week of training to go yet,” Hansen said.
“At this stage we expect him to be available, but we don’t know the team until Thursday.”
Only lock Patrick Tuipulotu and loose forward Jerome Kaino are unavailable, both due to injury.
The All Blacks released ten players to ITM Cup duties over the weekend, but little used openside Sam Cane and hooker Keven Mealamu were not available for Bay of Plenty and Auckland respectively.
“We’re one loosie own with Jerome out and we didn’t want to take the risk of losing another one,” said Hansen.
“He’s [Cane] fit enough, his testing results are good and he’s had a wee bit of rugby with us and we’re comfortable with him not playing this week.
“Kevvy’s been getting game time [(in the Tests) and he’s an old soldier who doesn’t need too much. A week off doesn’t hurt him.”
The major challenge for the All Blacks would be getting back to task after the high of thrashing Australia 51-20 at Eden Park 10 days ago.
“We have to put a big full stop on the performance two weeks ago and get ourselves mentally and physically right for this encounter on Saturday.”
Argentina are based in Auckland for most of the week, but Hansen said he was expecting a challenge.
“You could easily dismiss them because of what’s happened in the past, but anyone who is watching them will certainly respect them,” he said of the Pumas’ two close losses to South Africa this year.