Cape Town - Their playing styles are almost light years apart.
But there appears to be a rising chance now that only one of loose forwards Kwagga Smith and Rynhardt Elstadt will make the cut among the 31-strong Springbok party for RWC 2019.
Unless he has a curveball or two in store at Monday's keenly-awaited announcement, head coach Rassie Erasmus seems to have made it increasingly easier for pundits to narrow down his list of names for the tournament.
Having taken a squad of 36 to Bloemfontein for a further preparatory camp on Sunday, he just as quickly released a quartet of players - Marvin Orie, Thomas du Toit, Lizo Gqoboka and Andre Esterhuizen - for duty in the final round of Currie Cup matches on Saturday.
They will be decisive in establishing who the semi-finalists are to be in the domestic competition.
It cannot be ruled out that, in one or two of those instances, Erasmus simply feels it is worth giving them valuable game-time, and RWC berths not yet a totally forlorn hope.
But fiercer speculation now, and understandably so, is over which one of the current 32 in camp may be chopped to complete the likely final 31.
The split at present is 18-14 in favour of forwards and someone from the pack ranks could be the most endangered ... despite that being a far from fool-proof assumption.
But in that event, a tussle between the two more rookie elements of an otherwise seasoned arsenal of loosies, the now four-cap Lions tearaway Smith and two-appearance Elstadt, is a feasible enough element for speculation.
While Erasmus may yet choose to make a sacrifice from other positions, it would hardly be the most outrageous proposition if he went to Japan with five designated loose forwards rather than six.
That group would consist of highly proven figures Siya Kolisi (his anticipated captain), Duane Vermeulen, Pieter-Steph du Toit and Francois Louw ... plus one of Smith or Elstadt.
A credible sixth option, remember, is to exploit - if it were to come to that - the confirmed utility value of one of his locks, Franco Mostert, who has the necessary physical and pace-related requirements for blindside flank, where he has operated before at first-class level.
While all his 20 Springbok starts so far have been in the second row, "Sous" was no stranger to the side of the scrum during his yeoman Lions career in Super Rugby, even if a No 5 jersey for the red-and-whites was much more common.
In Elstadt's favour over Smith, if only one can get the nod, the tough Toulouse-based customer covers both No 6 and 7 in his flanker capacity, and is also no stranger at all to the second row when necessary.
Smith, meanwhile, is a notably smaller, more mobile loosie who can operate smartly either on the open-side flank or at eighth-man - and in a major crisis would not look massively out of place as a stop-gap backliner, especially given his formidable Sevens reputation as a speedy carrier.
Erasmus has invested quite heavily in Smith this season, giving him key Rugby Championship starts amidst his more pronounced "first team" against New Zealand in Wellington and then Argentina in the Salta title-decider.
My own gut feel, then, would be Elstadt as the one more at risk of staying behind, even if he would be a little unlucky considering the measured 2019 promise he has shown in a Bok jersey.
He has more in common with all the top-tier Bok loose forwards in largely robust, hard-yards playing style, whereas Smith (the proverbial "mole" and skilful, pacey linking element in attacking play) gives any squad an inviting point of difference.
The Lions marauder just seems likelier to be a major nuisance, including as a potentially prolific try-scorer, in the pool games that follow the high-stakes opener against the All Blacks, where the Boks can reasonably be expected to romp to victory over all of Namibia, Canada and Italy.
All that said, Smith and Elstadt both earning passages is still a solid enough scenario as well ...
The remaining 32-man Springbok squad for a training camp in Bloemfontein:
Schalk Brits (Bulls), Lood de Jager (Bulls), Pieter-Steph du Toit (Stormers), Rynhardt Elstadt (Toulouse, France), Eben Etzebeth (Stormers), Steven Kitshoff (Stormers), Vincent Koch (Saracens, England), Siya Kolisi (Stormers), Francois Louw (Bath, England), Frans Malherbe (Stormers), Malcolm Marx (Lions), Bongi Mbonambi (Stormers), Tendai Mtawarira (Sharks), Franco Mostert (Gloucester, England), Trevor Nyakane (Bulls), Kwagga Smith (Lions), RG Snyman (Bulls), Duane Vermeulen (Bulls)
Lukhanyo Am (Sharks), Damian de Allende (Stormers), Faf de Klerk (Sale Sharks, England), Warrick Gelant (Bulls), Elton Jantjies (Lions), Herschel Jantjies (Stormers), Cheslin Kolbe (Toulouse, France), Jesse Kriel (Bulls), Makazole Mapimpi (Sharks), S'bu Nkosi (Sharks), Willie le Roux (Toyota Verblitz, Japan), Handre Pollard (Bulls), Cobus Reinach (Northampton Saints, England), Frans Steyn (Montpellier, France)