South Africa could find themselves short of options at tighthead for the final game of the Rugby Championship due to injuries.
Jannie du Plessis has been ruled out of the clash with Argentina in Durban, while Frans Malherbe and Vincent Koch are both injury doubts.
Du Plessis picked up a knee injury in the loss to New Zealand, and will miss both the clash in Durban on the final weekend of the Rugby Championship, as well as a return fixture which will serve as a World Cup warm-up in Buenos Aires.
Meanwhile Malherbe has a bone bruise in his hip which he suffered during the Springboks' defeat in Australia, causing him to miss the All Black clash.
His replacement and Stormers teammate, Koch, is more optimistic about making it, after suffering a rib injury on debut last weekend.
Heyneke Meyer admitted that if they weren't back in time, he would be forced to look outside his squad, with alternative Coenie Oosthuizen still in rehab as he tries to be fit for the World Cup.
"We’ll have a look at Vincent and Frans in Durban and if they are not fit, we may have to bring someone in," said Meyer.
Elsewhere Meyer confirmed that Duane Vermeulen is on track to be ready for the World Cup, and the Springboks are expecting to have a full squad to pick from for the event in England.
Jean de Villiers, Fourie du Preez and Willem Alberts are all expected back for the next clash against Argentina and will have their fitness assessed on Monday as they complete the final phase of rehabilitation.
Although Du Plessis (knee) and Francois Louw (rotator cuff), along with Victor Matfield and JP Pietersen (both hamstring injuries) will miss both Tests against the Pumas, none of these injuries will put their RWC participation at risk.
Jan Serfontein (hip and knee), Marcell Coetzee (knee), Pieter-Steph du Toit (knee) and Steven Kitshoff (knee) will also be assessed on Monday with a view to being available to selection against the Pumas.
Frans Steyn is recovering well from a pectoral muscle injury and could be ready to play Argentina in Buenos Aires.
"All of these players have worked hard during their rehabilitation and although we still have to put them through a final assessment on Monday after we’ve re-assembled in Durban, I’m hopeful that they should be fit to face Argentina in at least one of the two forthcoming Tests," said Springbok team doctor Craig Roberts.
"We’re continuing to work very hard with Duane and Coenie and at this stage it’s looking very likely that we will have a full complement of players available for selection when the final squad for the Rugby World Cup is named at the end of August."
"It’s wonderful to see a number of players returning from injury and all of them will be considered if they are passed fit by our medical team," added Meyer.
"I’m also very glad Pieter-Steph is back. He was in the selection frame last week but after consultation between our medical team and that of the Cell C Sharks, we decided to stick to the original plan regarding his return to play, which is that he will turn out for his province in an Absa Currie Cup warm-up match on Friday.
"While it’s never ideal to lose experienced players to injury, it provides others with opportunities. We wanted to mix things up a bit in the two Tests against Argentina and the next players in line will now have to show they can perform at the highest level before we finalise the Rugby World Cup squad."