Former Scotland scrum-half Rory Lawson says selection choices in the centre pairings will give an indication as to how Gregor Townsend sets about overturning their dismal recent history against Ireland.
Following their 15-point loss to South Africa in the opening round, Scotland realistically need to win while denying Ireland a losing bonus point - aka, by eight points or more - to progress from the fiendishly difficult Pool B. [There is a fairly implausible alternative scenario, in which both Ireland and Scotland would progress, involving the Scots winning by 21 points while conceding four tries - alluded to here.]
Ex-scrum-half Lawson, who earned 31 caps for Scotland between 2006 and 2012, says Scottish rugby fans are feeling "hope" rather than "expectation" in advance of such of an enormous task, but adds that the widespread assumption of the international rugby community of an Ireland-New Zealand quarter-final may provide them with added impetus.
"From a Scottish public perspective, there's definitely hope. And there's a belief. I don't think there's expectation or an over-confidence," Lawson told the RTÉ Rugby podcast.
"Most knowledgeable rugby fans in Scotland realise the size of the task. If you're trying to build belief, it's probably best to avoid the fixtures in recent years. I think Ireland are eight on the bounce against Scotland.
"But I'm delighted that you lads have framed it as knockout rugby from the get-go. Because they'll certainly highlight where Ireland have come unstuck in knock-outs in previous World Cups.
"Scotland are capable of one-off performances. In fact, they're capable of consistent performances albeit Ireland are definitely a bogey team.
"I've got no doubt that Andy Farrell and his coaching team, his leadership team will have got into the granularity of where Scotland's threats are, where they've been successful historically. What's changed between the last match against Scotland and now.
"I expect Andy Farrell to have a squad that will come out, look to enforce physicality, get your nuts and bolts right around the set-piece, cause defensive pressure, cause kick pressure and try and force Scotland into errors, which historically they've been able to capitalise on.
"I know within that squad there will be a belief, albeit it's largely a free hit. You're playing against the number one team in the world. No one really expects Scotland to go and do it.
"Irish pundits, but also the pundits outside of Ireland and Scotland, are all talking about that quarter-final crossover involving New Zealand, France, South Africa and Ireland. For Scotland, that naturally becomes a fuel to fire you into the week."
Under Gregor Townsend, Scotland have become associated with a freewheeling, creative, loose game, reminiscent of their head coach's own playing career.
Since taking over as Scotland coach in summer 2017, Townsend has guided the side to famous victories in Paris and Twickenham but his head-to-head record against Ireland has been horrendous.
Their most recent win in the fixture was in the 2017 Six Nations, Vern Cotter's last campaign in charge, after which Joe Schmidt lamented that the Irish team bus had been too slow in snaking through Edinburgh. Ireland have won eight from eight since then.
As far as ending the run goes, Lawson feels that Townsend's selection call in the centre could be highly indicative.
So far, the Glasgow Warriors pair of Sione Tuipulotu and Huw Jones have been favoured, though Chris Harris and Cameron Redpath are also in the mix.
"I think when Gregor names his squad, we'll get a real idea of how they're approaching this game," he added.
"Do Scotland want to play a territorial game? A game whereby you have Chris Harris at 13, who is a defensive leader, often spoken about being one of the best defenders at 13 in world rugby. Or do they pick Huw Jones?
"If Chris Harris is named, we'll know it's going to be a bit of a territorial arm-wrestle. Hold out Ireland defensively or capture the opportunities when they come Scotland's way.
"Or if Huw Jones is picked, we know Scotland are going to give it a proper crack. They're going to try and stress Garry Ringrose and the outside defenders, and the Irish back three.
"Both jerseys are up for grabs in the centre. At the end of the game [against Romania] I really did feel that Cam Redpath could be a bit of a bolter within the selection this Saturday.
"He has shown up incredibly well for Scotland when given the opportunity. I think he's got a slightly different skillset to Sione Tuipulotu.
Potentially a little bit less dominant in the carry. But still a good carrier, he's got great footwork. He's excellent defensively and often goes for the strip tackle. He reads the game incredibly well.
"My gut will say that Gregor will go for Finn [at out-half], Sione and Huw Jones [in centres] but I wouldn't be too surprised if one of the other centres was named."
"But I'm delighted that you lads have framed it as knockout rugby from the get-go. Because they'll certainly highlight where Ireland have come unstuck in knockouts in previous World Cups"
A defeat - or even a narrow win minus a four-try bonus - will condemn Scotland to a second successive pool exit. While such an outcome would be disappointing, Lawson says it would be a world away from four years ago, given the extreme difficulty of the draw and the progression of the team in the interim.
However, the eventual manner of the loss to South Africa left a bad taste and they're keen to muster a better account at the weekend.
"In the post-match review of South Africa, Scotland came away thinking 'we didn't really get close to the middle of fourth gear'. That's where the disappointment lay.
The former Edinburgh half-back said: "They lost to South Africa fairly comfortably in the end but they didn't really fire the shots that you'd expect of a Scotland team.
"On Saturday, no matter what happens, they want to know that they've emptied the tank, they've fired the shots, they've chucked everything they can at Ireland on both sides of the ball and they'll be comfortable measuring themselves on that."
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