The All Blacks will lose their No 1 spot in the World Rugby rankings if they lose to the Wallabies in Perth on Saturday.
New Zealand have been sitting comfortably at the top of the rankings for the past decade, having usurped the Springboks on 16 November 2019.
The All Blacks have 91.54 rating points, 1.58 more than second-placed Wales. But a defeat by the sixth-ranked Wallabies in the first Bledisloe Cup Test of the year will cost New Zealand 1.66 points and subsequently drop them below Wales to second position in the rankings.
Wales, who won a Six Nations Grand Slam earlier in the year, will face England on Sunday and have to win or draw with their bitter rivals to topple the All Blacks at the summit of rankings.
World Rugby rankings:
1. New Zealand 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
Full rankings
How the rankings work
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