With another packed weekend of internationals looming, Scotland’s match against South Africa has the potential for a ranking reshuffle - but the tourists will need to create history in the process.
The Scots, after suffering their first-ever defeat by Samoa last week, have the chance to turn their fortunes around when they face the hosts in the four-nation tournament on Saturday.
Victory in Nelspruit would lift the Scots from 11th to ninth and demote the second-placed Springboks by up to two places, depending on other results.
History is against the tourists, however: although Scotland have beaten the Springboks as recently as 2010, they are yet to win a Test on South African soil.
Samoa, meanwhile, could edge closer to sixth-placed France if they continue their good form with a win over Italy.
Victory would lift the Pacific Islanders’ ratings total past the 80 mark but a win for Italy could see them rise one place to ninth.
Pumas on the prowl
Less than two ranking points separate the four sides placed nine to 12 in the world: Argentina, Italy, Scotland and Tonga.
Argentina, smarting from last week’s 32-3 defeat by England in Salta, could gain revenge this weekend in Buenos Aires and consequently gain one place in the rankings.
Another England win, however, would leave the tourists unchanged in fourth - depending on the result of South Africa v Scotland - and send Argentina out of the world's top 10.
With the rankings points taking into account respective positions in the table, Wales have everything to lose against world No.15 Japan.
Victory would leave the Welsh total unchanged but a Japanese victory would send the tourists down one place to sixth, while the Brave Blossoms would remain unchanged but with improved points.
France face New Zealand in Christchurch after losing by 10 points in the first Test in Auckland.
A French victory would not be enough to topple the All Blacks from top spot in the rankings, but would improve the French standing to fifth, edging out Wales.
Georgia’s 27-3 win over Uruguay in the IRB Tbilisi Cup earlier in the week has little effect on the standings, given the sides’ respective ranking at 16 and 21 in the world.
In the Elgon Cup, a victory by holders Uganda over Kenya would see the pair almost switching places. Uganda could leap from 41 to 37 and the latter drop to 40 in this annual fixture between the pair.
The IRB World Rankings are published every Monday at midday UK time.
- Monday 30 September 2013 - World Rankings
South Africa inch closer to rankings top spot
- Friday 27 September 2013 - World Rankings
Second within reach for Australia in rankings
- Monday 16 September 2013 - World Rankings
New Zealand increase rankings cushion at top
- Thursday 12 September 2013 - World Rankings
Ranking top spot at stake in Auckland
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- 28 July - Hong Kong's Dai Rees and first, Zimbabwe's Liam Middleton on the repechage
- 28 July - Pablo Lemoine on future of rugby in Uruguay
- 25 July - Barbados prepare for Commonwealth Games in Sutton Coldfield
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