Cape Town - Just how much smarter and more "worldly" have a battery of overseas-based Springboks become through their tenures abroad?
That is a tantalising question that should begin to be answered every bit as much from the Bok bench at Ellis Park on Saturday as from the starting line-up against Australia (17:05 kick-off).
While Toulouse-based new cap Rynhardt Elstadt on the open-side flank will have plenty of curious eyes cast onto him in the Rugby Championship opener - probably more so than veteran, Bath-employed loose forward colleague Francois Louw, who has had plenty of Test exposure in the last couple of seasons - it is off the splinters, more likely, that a group of foreign-based players will get the chance to solidly resurrect their credentials in this World Cup year.
The bench that head coach Rassie Erasmus has chosen for Saturday happens to be unusually laden - 50 percent of the eight - with personnel who are presently on the books of northern hemisphere clubs: Vincent Koch (Saracens), Marcell Coetzee (Ulster), Cobus Reinach (Northampton) and Frans Steyn (Montpellier).
That most of them have been short of a first-class gallop in recent weeks, due to the off-season in those climes, could go some way to explaining why he intends infusing them largely for later portions of the Wallaby contest, presumably giving the majority of them the last quarter or thereabouts to strut their stuff in the thin Highveld air.
But it will nevertheless be a fascinating little gauge of their hunger and sharpness to aid the Bok cause in a season culminating in the Japan-staged global extravaganza toward year's end.
What we already know, almost beyond dispute, is that all four cut it at the highest level when offering their A-games, if you like.
Someone like Steyn has especially little to prove: the burly utility back is the lone survivor of the entire, broader current Bok squad from the 2007 World Cup-winning one under Jake White's now distant tenure. (He was already a star then, and overwhelmingly remains that to this day.)
Or does he?
The single-minded, often unpredictable character, 32, has only contributed actively to the Bok cause three times - all as a substitute, in 2017 - in the last seven years, which is not exactly the greatest statement of green-and-gold commitment, whatever the varying reasons for his long absences.
At the same time, his string of skills (not to mention considerable physical presence) in several berths is not to be under-estimated and Erasmus has avoided being widely pilloried by either press or public for coaxing him back into the frame - a man of steel, in many senses - in 2019.
Steyn's conditioning is not always deemed tip-top, to put it quite mildly, so this match may provide some early signals of just how suited he is to playing a more fulsome role in Bok plans - possibly as a starter, something last witnessed at Dunedin in September 2012 - over the next few months.
But all of Koch, Coetzee and Reinach will be very much in the RWC 2019 picture as well if they get on the front foot performance-wise despite the likely limits of their duty, time-wise, on Saturday.
Koch, holder of 13 on-and-off prior caps between 2015 and 2018, is extremely highly regarded in England when he puts his mind most firmly to his destructive scrumming and carrying prowess, and certainly has it within him to challenge Frans Malherbe's status as incumbent Bok tighthead, even if he will also have to vault Saturday's starter at No 3 in the form of Trevor Nyakane.
Adaptable loosie marauder Coetzee, meanwhile, was a favourite much of the time of the head coach of the last World Cup cycle for South Africa, Heyneke Meyer, who got them to bronze in the 2015 event, and the former Sharks dynamo should be itching to add to his 28 Bok appearances - all earned before 2016.
He brings a bit of the intensity both as a ball-carrier and over-the-ball nuisance that Schalk Burger used to, and appears to have largely put behind him a saga of serious cruciate knee-ligament medical setbacks.
Reinach? While it is exciting that coach Erasmus has empowered a 23-year-old rookie, the Stormers/WP's Herschel Jantjies, with starting scrumhalf duty against Australia, the nippy UK Premiership-based player clawing his way back into broad Bok favour could go a long way to allaying fears over the depth of genuine quality in the key slot.
Another who has not represented the Boks yet in the latest four-yearly World Cup cycle, having earned his 10 caps before it, it will be interesting to see whether Reinach has curbed just a bit of his impulsive, frantic tendency - not always a drawback, mind - and matured as a game manager.
That is a likely event considering his burgeoning experience on slower European pitches where more conservative game-plans are often the order of the day.
Throw in the inspiring tale of someone like home-based loosehead prop Lizo Gqoboka of the Bulls almost certainly earning a maiden cap - the Transkei village-born player only began playing the sport some 10 years ago - also off the bench this weekend, and there should be very little reason indeed for any Bok supporters to doze off by the three-quarter mark on Saturday, whichever way the contest is leaning ...
15 Warrick Gelant, 14 S'bu Nkosi, 13 Jesse Kriel, 12 Andre Esterhuizen, 11 Makazole Mapimpi, 10 Elton Jantjies, 9 Herschel Jantjies, 8 Francois Louw, 7 Pieter-Steph du Toit, 6 Rynhardt Elstadt, 5 Lood de Jager, 4 Eben Etzebeth (captain), 3 Trevor Nyakane, 2 Bongi Mbonambi, 1 Tendai Mtawarira
Substitutes: 16 Schalk Brits, 17 Lizo Gqoboka, 18 Vincent Koch, 19 Marvin Orie, 20 Marcell Coetzee, 21 Cobus Reinach, 22 Frans Steyn, 23 Dillyn Leyds
15 Tom Banks , 14 Dane Haylett-Petty, 13 Tevita Kuridrani, 12 Samu Kerevi, 11 Reece Hodge, 10 Bernard Foley, 9 Nic White, 8 Isi Naisarani, 7 Michael Hooper (captain), 6 Lukhan Salakaia-Loto, 5 Rory Arnold, 4 Izack Rodda, 3 Sekope Kepu, 2 Folau Fainga'a, 1 James Slipper
Substitutes: 16 Jordan Uelese, 17 Harry Johnson-Holmes, 18 Taniela Tupou, 19 Rob Simmons, 20 Jack Dempsey, 21 Will Genia, 22 Matt To'omua, 23 Kurtley Beale