Youngsters will 'grow an arm and a leg' following Argentina win - Hansen

New Zealand coach Steve Hansen felt his side learned important lessons in Saturday's 36-10 victory over Argentina.

Already confirmed as the winners of the Rugby Championship following the 27-27 draw between South Africa and Australia, the All Blacks charged into a 29-3 half-time lead in Buenos Aires.

However, it was a different story in the second period as Argentina made life tough for a New Zealand side missing several experienced players.

"We took some risk in leaving some people at home, because we know at the end of the tour we need to have some fresher legs, but we got the rewards for that because the young guys did a great job in the first 40 minutes and then had to fight their way through some ugly stuff in the second 40," said Hansen.

"They'll grow an arm and a leg because of that. It's not an easy place to play, so you can't just rock up and have it sweet and easy."

The All Blacks saw Matt Todd and captain Kieran Read sent to the sin bin as Argentina rallied.

"Losing the skipper was great for us, because someone had to lead the team," Hansen reasoned. "I think for the first five of the 10 minutes [Read was off the field], everyone thought they were [leading], rather than just doing their job, but you come through those things and you grow and you learn.

"The whole evening's been good for us. We did a lot of things well - I thought we attacked well, we defended courageously at times."