A shock defeat for the All Blacks to the Wallabies in Perth on Saturday night will be a double blow for the World Cup winners.
If Steve Hansen's men fall to Australia in the opening Bledisloe Cup test it will mean that they will give up their number one spot to Wales.
This follows their 16‑16 draw to South Africa in Wellington where the All Blacks now hold a 1.58 point lead in the rankings over Wales.
A loss in Perth would see the All Blacks drop by 1.66 points and into second spot, according to Wales Online.
However it could only be short lived if Wales don't beat England at Twickenham in the first of two tests dubbed as 'warm‑ups' ahead of the World Cup.
Last month Hansen says following their tight win against Argentina that rankings mean nothing to them ahead of the Rugby World Cup.
The All Blacks have been on top spot for almost a decade now after defeating the Springboks three straight times early in the 2009 rugby season.
The All Blacks will face Australia at 9.45pm Saturday while Argentina will host South Africa at 7.40am Sunday.
World Rugby rankings:
1 ‑ All Blacks ‑ 91.54
2 ‑ Wales ‑ 89.96
3 ‑ Ireland ‑ 88.69
4 ‑ South Africa ‑ 86.30
5 ‑ England ‑ 86.27
6 ‑ Australia ‑ 81.91
7 ‑ Scotland ‑ 80.17
8 ‑ France ‑ 79.42
9 ‑ Fiji ‑ 76.98
10 ‑ Argentina ‑ 76.81
NZ Herald
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