Cape Town – The likelihood of the Springboks playing host nation Japan in a World Cup quarter-final rather than Ireland suddenly swelled dramatically on Saturday … though guard against popping too many pinotage corks yet.

For all the swift, shrewdly diplomatic talk from Bok coach Rassie Erasmus about how difficult a last-eight tussle with the Brave Blossoms would be, we all know the national team would bite your hand off to play Japan rather than the Irish in some three weeks’ time.

It could happen, after Pool A was thrown into intriguing chaos at Shizuoka by the stunning, deserved 19-12 Japanese victory over Ireland, in a scene reminiscent of their Springbok giant-slaying at Brighton in RWC 2015.

The side led on Saturday by Pretoria-born flanker Lappies Labuschagne now top the group with two wins from two, and a three-point log lead over the much more fancied Irish with two matches each left to play.

Even if they beat both Samoa and Scotland without a bonus point, Japan would progress to 17 points: safely out of reach of Ireland who can only reach a maximum of 16 from here (assuming they beat Russia and Samoa in “maximum” fashion).

But do the hosts have it within them to triumph on both occasions?

They have a useful full week’s turnaround now to the challenge of the Samoans next Saturday (12:30 SA time, City of Toyota Stadium) and then a further eight days to October 13 and the pool-closing Scottish clash (12:45 SA time, Yokohama).

So the good spacing of their schedule means head coach Jamie Joseph has fewer squad rotational challenges to contend with than some other countries.

Nevertheless, Japanese wins - in both instances - should not be taken for granted.

For one thing, the Samoans are a traditionally rugged, committed side to encounter and they have only played one match so far themselves: a 34-9 triumph over Russia who, in turn, had been beaten 30-10 by Japan in the opening match.

It firmly tells you that Japan v Samoa could be a very tightly-contested affair.

In Japanese favour is that they now lie eighth on the (sometimes controversial) World Rugby rankings, whereas Samoa are 15th.

Also, Japan earned a comfortable 26-5 victory when the two locked horns at the 2015 World Cup, in Milton Keynes.

That said, Samoa still lead overall bilateral bragging rights 11-4.

When it comes to Scotland, Japan have not yet beaten them once in seven Tests, so they would have to make a similar sort of history as they did against the Irish.

The last time they did battle, in a two-Test series on Japanese soil in 2016, the Scots won 26-13 (Aichi) and 21-16 (Tokyo).

In short, then, Japan still have it all to do if they are to sensationally top the group and make the Boks and All Blacks (the latter now potentially facing the stiffer hurdle against Ireland, if they win Pool B as expected) adjust their quarter-finals thinking.

South Africa move on to Shizuoka for Friday’s meeting with Italy, fuelled by their first tournament win (57-3) against minnows Namibia after the opening setback against the All Blacks that may yet prove a major blessing in disguise.

The largely second-string Boks were way too powerful for their neighbours who, with respect, were almost like “Country Districts” foes to a major power on the day, even if their spirits seldom flagged and they prevented the sometimes error-plagued Boks from truly running away with the contest.

Erasmus is expected to resort back to the nucleus of his senior personnel for the Italian date.

If the Boks do manage to escape Ireland and play Japan instead (having just beaten them 41-7, ahead of the tournament), inevitable comparisons will be made with their “kind” 2007 route to glory in France, when they faced Fiji in a quarter-final and then Argentina in the semis.

But a few things have to fall into place yet for that scenario to come into play …

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