New Zealand could close to within fourth tenths of South Africa at the top of the IRB World Rankings if they can make it five wins in a row against Trans-Tasman rivals Australia when the sides come face to face in Sydney on Saturday.
The All Blacks currently sit 1.77 rating points behind the world champions, having lost their number one spot following back to back defeats by South Africa in Bloemfontein and Durban in this year's Tri Nations.
Those two defeats mean victory over the Wallabies is a must for New Zealand at the ANZ Stadium in Sydney this weekend if they are to keep alive hopes of retaining their Tri Nations title.
New Zealand have already beaten Australia 22-16 in Auckland in the Tri Nations' opener and will be looking to repeat their most recent success on Australian soil - a 28-24 victory in Brisbane last September that clinched a ninth crown.
One of New Zealand's try scorers in that come from behind victory was Dan Carter, the fly half who returns to the All Black fold after six months out with a ruptured Achilles to face a Wallaby side shorn of injured captain Stirling Mortlock.
If Carter can inspire the All Blacks back to winning ways then New Zealand could - with a victory margin of more than 15 points - cut the deficit to South Africa to only 0.36 rating points.
However if Australia can repeat their last win over New Zealand - ironically in Sydney last July when Robbie Deans' side won 34-19 - then they could close to within a similar margin of the second ranked All Blacks.
Australia currently trail New Zealand by 3.57 rating points, but a win by more than 15 points would reduce this to a mere 0.39 points and increase their cushion over leading northern hemisphere nation Ireland to in excess of four points.
In the event of an emphatic Australian victory, South Africa's position as the number one side in the IRB World Rankings would be strengthened with their lead over the All Blacks growing to 3.36 points.
The IRB World Rankings update every Monday at 12:00 UK time.
