South Africa head into Saturday's Rugby Championship opener against Argentina in Buenos Aires with their World Rugby number-one ranking under threat. The Springboks currently sit on 93.96 points — a 10.83-point buffer over New Zealand's 92.28 — but that cushion counts for nothing if Los Pumas cause an upset.
Because of that differential, a Springbok victory — by any margin — yields zero ranking points for South Africa. The rating system only moves against them. A defeat by 15 points or fewer drops the Boks to 91.96, handing New Zealand top spot. A loss by more than 15 points is more damaging still, leaving South Africa on 90.96 — 1.32 points adrift of the All Blacks. It would also be the Springboks' fourth defeat on Argentinian soil.
Argentina, meanwhile, have plenty to play for beyond bragging rights. Victory lifts Los Pumas above Scotland into sixth; a winning margin exceeding 15 points also moves them above England into fifth. Their floor is seventh regardless of how Australia fare against Japan earlier on Saturday, as the Wallabies cannot accumulate enough points to close the gap.
New Zealand are in Cape Town on Friday night to face the Stormers, but that fixture carries no ranking implications.