South Africa lost three wickets in the morning session of day four in Guwahati but stretched their overall lead to 395 runs in the second and final test against India on Tuesday.
The visitors were 107-3 at tea and looking set for a 2-0 series sweep after winning the opener in Kolkata inside three days.
Tony de Zorzi was batting on 21 at the break with Tristan Stubbs on 14 at the other end with the world test champions appearing in no rush to declare their second innings.
However, their top order looked ill at ease against the turning ball on Tuesday after resuming on 26 for no loss in the first ever test at Barsapara Cricket Stadium in northeast India.
Ryan Rickelton (35) and Aiden Markram (29) added 59 runs for the opening stand before left-arm spinner Ravindra Jadeja removed both the batters.
Rickelton was snared at cover, while Markram was done for by a Jadeja delivery that drifted in from wide of the crease and spun past the bat to peg back the off stump.
Off-spinner Washington Sundar had Temba Bavuma caught at leg slip for three and could have claimed the wicket of Stubbs too had Rishabh Pant not missed a stumping opportunity.
Pant is leading India in the absence of their injured skipper Shubman Gill.
(Reuters)