Matfield said on the Rivals podcast, "We forget that all these teams are so much closer these days.
"If you are not on your game, you will get beaten.
"Argentina beat New Zealand in New Zealand last year; they beat South Africa there [in Argentina]. They beat the British & Irish Lions in that Test match.
"Unfortunately for them, it is just that consistency. If they can get their consistency right, they are a threat. If they get that momentum in a game, it opens up, it gets loose, they are a very dangerous side."
Matfield said the fact that the All Blacks lost will make them more determined against the Springboks, and it is going to be 'a massive game.'
Australia had been an interesting team to play. It felt in their second Test, in Cape Town, that South Africa was about to go [pull away].
"But Australia just stick in there. They keep coming back, they don't make mistakes, and when they get an opportunity, they use it; so, they are an interesting team to play against at the moment.
"There's nothing flashy about them, they're just accurate in everything they do."
They would cause more upsets, but they would also feel greater expectation on them, and that would add pressure to their performances.
Matfield said the area the All Blacks need to clean up is the high ball.
"These days, we all talk about attack, we all talk about line speed, but that aerial battle is so big in this modern game, especially now that you can't block it. It was not just the aerial battle, but all the scraps went to Argentina.
"They get energy off that. The moment they start getting those loose balls a little bit quicker, then the footwork comes into play, those guys run onto the ball, they get momentum, then you are in trouble, because they speed up the game as well.
"For New Zealand, if they can sort out that, because it is also something that takes energy away. If the forwards need to run back all of a sudden we are not winning and now we will need to work harder, we need to get into line, we want to get the ball back. They may be rush a little too hard to try and get it back and make mistakes so the momentum kept going with Argentina."
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