"You've got to remember we are four or five in the world. I don't think we are at this stage the benchmark to compare teams with," Erasmus said.
"When they get to the likes of England, Wales and Ireland I think New Zealand will have some stiff competition going through to the finals.
"There's teams that can handle their kicking game and specific things they do better than we do.
"We've played them now six times in the last two years so we know one another really well but I definitely think they are the favourites for the World Cup and we never had a doubt about that. We are creeping a little bit closer in challenging them.
"They will have different challenges against teams like England, Ireland and Wales who bring different pressures. We bring physicality – they handled our maul pretty well, they handled our scrum and kicking game well but when you play teams like England and Wales they have totally different strengths.
"By all means I think without a doubt New Zealand are favourites but they will have different tactical challenges against the northern hemisphere teams and it will be interesting to see how they handle that."
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In the lead up to this match Erasmus and the Boks attempted to put pressure on French referee Jerome Garces by suggesting the All Blacks enjoyed favourable decisions when they were world No 1.
While he praised the All Blacks, Erasmus again appeared to make the assertion his side did not get the rub of the green, despite Garces overlooking a clear and cynical yellow card offence with the All Blacks hot on attack in the first half.
"Two tries to one they definitely deserved to win the game but when you concede 11 penalties to two you're always going to struggle to beat New Zealand. Discipline was our biggest downfall but I don't think we can moan about anything.
"It's a combination of them putting pressure on us and us not handling pressure well.
"The moment they have scoreboard pressure you have to play from your half and they make it really tough."
No team has ever gone on to win the World Cup after losing a pool match but Erasmus is confident the Boks can respond.
"Yes I think we can fight back - we fought back after halftime from 17-3 down. I've seen South African teams get 50 points put on them from there."
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