World champions South Africa launch their November tour in Scotland knowing the prospects of a shock loss at Murrayfield on Sunday could depend upon "two of their own".
Scotland's starting team features wing Duhan van der Merwe, his adopted country's all-time leading try-scorer, and prop Pierre Schoeman, two South Africans who became eligible for the Dark Blues under World Rugby's residency rules.
The hosts will also be captained by Australian centre Sione Tuipulotu, qualified for Scotland through his Scottish grandmother. No 8 Jack Dempsey has played for the Wallabies, while New Zealand-born full-back Tom Jordan will make his first Scotland start after coming off the bench during last week's 57-17 rout of Fiji.
Scotland, however, will be bolstered by Toulouse's Blair Kinghorn and Bath's Finn Russell after the native backs missed the Fiji game because it took place outside World Rugby's designated window for November internationals.
Professional rugby union has been hard for Scotland, with the domestic game sustaining just two senior clubs, in Edinburgh and Glasgow, thereby reducing the pool of available local talent.
Meanwhile, the difficulty of forging a career in rugby-mad South Africa – long a superpower of the game – and the relative weakness of the Rand as a currency can lead players to take their chance elsewhere.
But Springbok centre Andre Esterhuizen has no regrets, even though the 30-year-old will be winning just his 19th cap on Sunday after spending much of his career competing for a test place with the outstanding Damian de Allende.
"I'd much rather have my 18 caps for the Springboks than 70 caps for a different country that I'm not actually born in," said Esterhuizen.
"I love this country and this team. I'm very content with where I'm at."
He added: "Damian is there, Lukhanyo (Am) is there –- there's so many players that can play 12 (inside centre)...It's also very healthy for the squad."
Esterhuizen insisted he meant no criticism of those who had taken a different path.
"It's also easy for me to say it in hindsight," he said. "If I left earlier and that opportunity came I don't know what I would have done...You also need to make money out of rugby, so there's two different sides to it."
De Allende and fellow regular test backs Jesse Kriel, Kurt-Lee Arendse, Aphelele Fassi and Cheslin Kolbe have all been left out, with just a six-day turnaround before South Africa face England at Twickenham.
South Africa have been pioneers in packing the bench with forward power, with Grant Williams the lone back among their eight permitted replacements in Edinburgh.
Eben Etzebeth captains the side in a record-extending 129th cap. The veteran lock is backed up by a bench where Malcolm Marx, Gerhard Steenekamp, Vincent Koch, RG Snyman, regular skipper Siya Kolisi, Pieter-Steph du Toit and Jasper Wiese form the latest version of the Springbok 'bomb squad'.
'BIGGEST CHALLENGE IN WORLD RUGBY'
Scotland coach Gregor Townsend avoided the thorny issue of eligibility by saying "there's nothing we commented upon or talked about with our group".
But he was more forthcoming about the task confronting his side against South Africa, who won the 2024 southern hemisphere Rugby Championship after completing back-to-back World Cup triumphs in France last year
"It is the biggest challenge in world rugby right now," he said.
The former Scotland playmaker added that, for all their renowned physicality, South Africa now had an "extra dimension".
"They are very innovative around their set-piece plays, they're moving the ball wide at pace and they have some very talented and dynamic players," Townsend explained.
South Africa beat Scotland 18-3 in a World Cup pool match but only led 6-3 at the break, and Springboks supremo Rassie Erasmus is forecasting an "epic battle" on Sunday.
"They're a team that never stop fighting," he said of Scotland.
"In the Rugby World Cup last year we were only three points up against them at halftime, and with the new dynamic they have brought to their game, we know it's going to be an 80-minute battle."