Springbok locks Eben Etzebeth, right, and Lood de Jager, left, are set to play their first Test since November against Argentina on Saturday.

The Springboks' engine room has received a massive injection of world-class pedigree and experience just as an injury crisis threatened to stretch the world champions' second-row depth ahead of Rugby's Greatest Rivalry Series against the All Blacks.

The return of seasoned veterans Eben Etzebeth and Lood de Jager for Saturday’s Test against Argentina provides an invaluable boost, offering immense relief following injuries to frontline locks such as RG Snyman and Jean Kleyn.

The Springboks started the season with flanker Pieter-Steph du Toit having to move to lock at the 11th hour following Etzebeth's late withdrawal. Since then, utility forward Cobus Wiese has made quite the impression in the No 4 jersey against Scotland and Wales, using his powerful carrying ability to make an impact.

Losing operators of Snyman and Kleyn's calibre would destabilise almost any pack in world rugby. Snyman’s offloading dynamism and Kleyn’s uncompromising physical edge are difficult commodities to replace. However, the simultaneous return of Etzebeth and De Jager in Buenos Aires immediately restores an aura of physical intimidation and tactical authority.