Victor Matfield is set for three weeks out of Super Rugby action with the Bulls, after seeing knee specialist Daan du Plessis.
Matfield has played six matches for the Bulls this season, including time coming off the bench.
The 37-year-old has been expected to go to the Rugby World Cup with South Africa later this year, which made the outcome of his meeting on Tuesday all the more important.
Matfield will undergo surgery on Wednesday to remove some cartilage from his knee, ruling him out for three weeks.
"The idea is to get it done now to avoid problems going forward – especially with the World Cup getting closer as well," said team doctor Org Strauss.
Meanwhile, Springboks Flip van der Merwe and Arno Botha have returned to full training following a pectoral and hamstring injury respectively and will be considered for Saturday's Super Rugby match against the Reds.
They will join the likes of Jan Serfontein and Handré Pollard, who missed last weekend's clash against the Emirates Lions, but Jesse Kriel (ribs), Burger Odendaal (arm), JJ Engelbrecht (pectoral), Trevor Nyakane (shoulder) and Jacques du Plessis (muscle spasm) all picked up light niggles on the weekend and will sit out training Monday.
All of them will be back in action on Tuesday, as well as Basil Short, who recovered from concussion.
Akona Ndungane (broken hand, 13 April), Lappies Labuschagne (shoulder, 13 April), William Small-Smith (foot, 20 April) and Travis Ismaiel (ribs, 20 April) will return to action before the end of the month.
Pierre Schoeman (ACL, 31 July), Bandise Maku (pectoral, 31 July), Carlo Engelbrecht (ankle, five weeks), Werner Kruger (ankle, five weeks), Duncan Matthews (ACL, 31 July), Ruan Steenkamp (PCL, 31 July), Ryan Nell (ACL, 31 August) are all on the long-term recovery list.