The once-feared Springboks engine room is in line for another overhaul on Saturday when the severely depleted world champions clash with the All Blacks in the second leg of their Tri-Nations rugby road trip.
Flip van der Merwe and Alistair Hargreaves, the locking duo which started Saturday's 39-20 loss to the Wallabies, both sat out training on Monday.
It was the side's second last run before South Africa leave for Wellington on Wednesday.
Van der Merwe popped a rib cartilage against Australia and is highly unlikely to recover, although the prognosis on Hargreaves' abdominal muscle strain was more positive.
Victor Matfield and Bakkies Botha are resting back in South Africa and Johann Muller is also out of action with a hamstring injury.
The Springboks assistant coach Gary Gold admitted the second row was a major cause for concern ahead of the first of three potential clashes with the All Blacks this year.
The Bulls veteran Danie Rossouw is in contention to switch from the blindside flank and, if Hargreaves is also ruled out, then a Test debut looms for Gerhard Mostert.
It turned out Springboks head coach Peter de Villiers was serious on Saturday night when he stated there were no locks left in South Africa as he mulled over the injury toll inflicted by the Wallabies.
Mostert, 26, had to be summoned from Paris, where he had spent less than a week at his new club Stade Francais since leaving Durban at the end of the Super Rugby season.
He arrived yesterday via Amsterdam and Hong Kong and ran off the jetlag during a light session at North Sydney Oval.
With 21 World Cup contenders nursing injuries back home, another casualty toll from the Tri-Nations opener was hardly ideal for the side's management.
Asked if the Springboks were capable of rebounding from an unsatisfactory performance against the Wallabies, Gold did not sugar coat the predicament.