In addition to confirming Kolisi’s retention as captain, Erasmus said full-back Willie le Roux and wing Cheslin Kolbe are both fit to face Ireland in the opening Test in Pretoria on 6 July.
“Willie and Cheslin are clear to play, but we’ll have to manage [wings] Edwill van der Merwe and Makazole Mapimpi. Both of them stand a chance of being available for Ireland,” said Erasmus, who returned as head coach in February after Jacques Nienaber’s departure to Leinster.
“We also have to manage [scrum-half] Faf de Klerk, but [utility back] Canan Moodie will only be available for the second Test.”
Erasmus named his 39-man squad for the Ireland series on Tuesday. After the opening Test in Pretoria, the sides meet in Durban on 13 July.
Ireland, whose three straight wins over South Africa includes a 13-8 success in last year’s World Cup pool stage, arrived in Johannesburg on Wednesday.
“If there’s one team that has the upper hand, it’s them,” Erasmus said of the Irish.
“We haven’t beaten them since 2016.”