British and Irish Lions' warm-up game against Vodacom Bulls scheduled to be played in Pretoria on Saturday has been postponed following a Covid-19 outbreak.
The second Test fixture between South Africa and Georgia is also under doubt with seven players - Lood de Jager, Marvin Orie, Frans Steyn, Handre Pollard and Frans Malherbe along with six management members including head coach Jacques Nienaber have been reported positive for the virus in the latest round of testing.
It is also confirmed that Georgia, who played the Boks in last weekend's encounter have four positive cases with Bulls also having five positive cases.
The Springboks have already suspended their training with the entire squad placed under isolation.
"Four Bulls players and one member of management returned positive tests which, in combination with their close contacts, made it impossible for them to field a team, according to series safety protocols," read a statement.
"Series regulations make provision for additional midweek matches to be added on agreement between the organizations.
"Meanwhile, four positive results among the Georgian team and four additional positive tests among Springbok players plus six among management, including head coach Jacques Nienaber, and one masseuse, have further complicated planning."
"These positive results are a setback and have underlined the danger of transmissibility of the delta variant," said South Africa Rugby Chief Executive Jurie Roux.
"The Springboks' second Test against Georgia is now in serious doubt, but we will wait for the MAG to consider the data and we will make the final decision tomorrow.
"The priority is to maintain the integrity of the Test series and we will continue to focus on that."
The South Africa board also confirmed that Lions' game against Sharks at Emirates Airlines Park will go ahead as scheduled.