Springbok captain Jean de Villiers for South Africa's final June test match against Samoa at Loftus Versfeld in Pretoria on Saturday.
De Villiers injured his right sterno-clavicular joint and second rib early in last weekend's victory over Scotland in Nelspruit.
"Jean was able to continue playing but was in some discomfort after the game," said Springbok team doctor Craig Roberts.
"He could not train on Monday and we will reassess him in the next few days before making a final call on his availability to face Samoa."
Apart from the injuries to De Villiers and loose forward Arno Botha, who has been ruled out of rugby for the rest of the season with a serious knee ligament injury, there were only a few more bumps and bruises from the Scotland match.
Pierre Spies and Jannie du Plessis both sustained lacerations to the face, while Eben Etzebeth complained of mild discomfort in his AC joint.
These three players, as well Willem Alberts, did not take part in the full training session on Monday.
"Willem is returning from a side strain and his workload during the early part of the week will be managed, but at this stage he's looking good for a possible return this weekend," said Roberts.
Springbok coach Heyneke Meyer said no risks will be taken with any player who is not 100% fit to play.
"We have a very good medical team and will see how Jean and Willem react to treatment this week before making a final call on their availability for Saturday's match against Samoa, which we're expecting to be quite physical," said Meyer.
"Injuries are part of the game. We already lost four injured players during this series " Pieter-Steph du Toit, Jano Vermaak, Francois Hougaard and Arno.
"Furthermore, we could not consider a number of other injured players who were part of our training group in the last year, like Frans Malherbe, Pat Cilliers, Duane Vermeulen, Cobus Reinach, Johan Goosen, Jaco Taute, JP Pietersen and Frans Steyn."