Given the desire to avoid France in a potential World Cup quarter-final, it's no exaggeration to say Ireland are heading into the biggest game yet of the Andy Farrell era.
On the face of it, Ireland appear to be in a good place physically as we lead into the big Pool B meeting at Stade de France; Dan Sheehan appears to be on track to play after recovering from a foot injury, Jack Conan is also making good progress with the number 8 more likely to feature against the Scots in the final game of the pool, while Finlay Bealham is on course to be available after coming through his head injury assessment.
Farrell will name his team on Thursday, two days out from their meeting with the world champion Springboks, and while his the majority of his matchday 23 looks locked in, there are a coupe of places up for grabs in both the starting XV and on the bench.
One of those is at hooker where Farrell appears to be spoiled for choice, with three players fighting it out for two spots.
Dan Sheehan is expected to be put straight back into the starting side after his foot injury, with Rob Herring (below) and Rónan Kelleher likely to contest the 16 shirt.
"The Rónan Kelleher Rob Herring one is a real brain teaser in the sense that there's subplots to it," former Leinster, Connacht and Ulster lock Mick Kearney told the RTÉ Rugby World Cup podcast.
"Obviously Rob Herring is Irish and has played for Ireland but there's the added motivation of him being born in Cape Town.
"The idea of him playing his country of birth, you speak to the likes of Richardt Strauss who has done it in the past, he’ll tell you it’s a game he couldn’t have been more up for from a motivational point of view.
"That’s not to say Kelleher won’t be up for the biggest game of the World Cup far, but if I was choosing who was going on the bench, I'd probably go with Rob Herring for that reason, just because I feel that he’ll have that added bit of motivation, to prove a point to family and mates back in South Africa."
BJ Botha, who won the World Cup with the Springboks in 2007, agreed with Kearney that Herring is just about leading Kelleher in the race for a place in this week's squad.
"Not only that from motivation perspective, but I think Rob's a stronger scrummager technically and his experience up front will be key. There’s no doubt you can put him there and he’s been consistent in that position. That’s what you require against South Africa coming off the bench."
Another position that could be up for grabs is at scrum-half.
Jamison Gibson-Park has been first choice behind the scrum for Farrell when fit in the last two years but Conor Murray's (below) recent form has brought him back into the picture to start against the Springboks, according to former Ireland flanker Stephen Ferris.
However, Kearney told the podcast that he'd be inclined to start the Leinster scrum-half, and use Murray's game management skills for the second half.
"It's tough... I’d go with Jamison Gibson-Park, just for his ability to move the ball," he added.
"If we do win collisions in attack and get South Africa on the back foot, Gibson-Park is the man to play nine for that game.
"If we’re 50-60 minutes in, it’s a great tome to bring Conor Murray on, just with the level of control he has, particularly with his kicking game.
"The charge-down he had against Tonga, I think it’s just the second time I’ve ever seen him be charged down in a game, it’s a credit to his ability in the area."
The other big selection call Farrell has to make will be the position of Tadhg Beirne.
The versatile forward started at blindside flanker for the opening win against Romania before moving back to his traditional role of second-row on Saturday.
On last week's podcast, Botha believed that an Irish pack with Beirne (below) in the back-row and one of Iain Henderson or Joe McCarthy at lock would be preferable to the Springboks.
However, the Ex-Ulster and Munster prop said he could see the merit of holding a "gamebreaker" like Josh van der Flier back on the bench in order to counter the strength South Africa will likely have in reserve.
We know what's coming off the bench [for South Africa], and yes Marx isn’t there, but the rest [of the Bomb Squad] are. With Van der Flier coming off the bench, if you have it the other way around, you have experienced guys coming of the bench, but maybe not these gamebreakers you rely on.
"As we’ve seen time and time again, the bench changes the game, and that could be one that helps Ireland."
And Kearney says he would hold the World Player of the Year back in reserve, to allow Ireland start with extra size in their lineout and scrum.
"I probably would be inclined to move Tadhg [Beirne] to six and have Pete [O'Mahony] at seven, but that's purely from a lineout point of view. You obviously have four very good options.
"It’s a huge call, it’s a huge call and I don’t envy Andy Farrell having to make it.
"The only thing I would say is that Josh would be like a coiled spring coming on for the last 25/30 minutes. It’s a big risk, but this week in particular in my opinion it’s 'no set-piece, no win’. I’m a second row so I’m slightly biased, but in my mind everything else is irrelevant."
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