Cape Town - The intriguing thing about quarter-finals, apart from signalling the start of nerve-jangling knockout play at the World Cup, is the potential for them to represent “last game” opportunities at Test level for veteran players.

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If you reach the semis, after all, you’ve still got a guaranteed additional game ahead, whether it be the final or the playoff for bronze.

But at the last-eight stage, you run the risk of exiting the tournament altogether ... with an almost indecent sense of suddenness, especially if you’ve been the victim of an upset result.

Touch wood now, South Africans: the Springboks really should subdue Japan in Tokyo on Sunday (if you’ve been following Sport24, I’ve been bullish all week on that front) and advance to the last four.

But if we do suffer another “Brighton”, we might also know pretty quickly from the post-mortem which Boks have simultaneously opted to step down from international (or possibly all, in some cases) rugby.

It is reasonably common - even if they have alerted the administrators, team brains trust and colleagues quietly beforehand - for players bowing out to only do so publicly upon completion of a major event, like RWC.

Apart from the very obvious case of Schalk Brits, the admirable 38-year-old who was basically coaxed out of retirement to boost the Boks’ tournament cause (vibrantly, colourfully!) one last time, there were no already on-record swansong players in the SA ranks as they entered the knockouts.

For one thing, Rassie Erasmus’s seemingly harmonious, close-knit squad is very largely made up of players with at least one further four-year “World Cup cycle” within them.

The players (besides Brits) most likely to pull the plug on Tests after RWC 2019 would be Francois Louw and Tendai Mtawarira (both currently 34), Duane Vermeulen (33) and Frans Steyn (32).

If I were a betting man I’d venture that long-time Bath-based Louw is presently the likeliest to quit the Boks after the tournament - well knowing, among other things, that South Africa remains a proud “factory” in production of dynamic young loose forwards.

But the “Beast”? He has cut a resurgent figure under Erasmus, so what price the chance (OK, perhaps still an outside one) that he is thinking of a rare, second crack at a British and Irish Lions series a dozen years on from his stellar first in 2009? They are due on our shores in 2021, when he would be 36 ... not too outrageous for a front-ranker keeping himself suitably fit.

As for Vermeulen, he has not yet sampled a Lions series, having begun his Test career considerably later than was deserved, and he may be tempted to push on toward it as well.

The famously unpredictable character who is Steyn? Um, well, who knows ...

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