The Springboks will be holding their breath as they await confirmation on the severity of captain Siya Kolisi's hamstring injury. Springbok captain Siya Kolisi is a doubt for Rugby’s Greatest Rivalry series against the All Blacks after he went off injured in the Boks’ one-off Test against Argentina in Buenos Aires on Saturday night. But Erasmus had a more positive view, saying: “Siya pulled his hamstring. Kolisi added that this was the perfect build-up for the Boks ahead of their participation in Rugby’s Greatest Rivalry series, with the first Test against the All Blacks in two weeks’ time. “This (game) was great preparation for that (Rugby’s Greatest Rivalry).