India look good for a huge first innings lead as South Africa struggled to reach 197 for eight at tea on the third day of the second Test after spinners Ravichandran Ashwin and Ravindra Jadeja kept up the pressure created by the pacers.
South Africa are still 404 runs behind India's gigantic first innings score of 601 for five declared.If the morning belonged to Mohammed Shami's hostile spell and an acrobatic catch from Wriddhiman Saha, the afternoon session was all about relentless pressure created by Ashwin (2/49 in 21 overs) and Jadeja (1/51 in 25 overs).
South Africa's most experienced pair of skipper Faf du Plessis (64 off 117 balls) and Quinton de Kock (31 off 48 balls) tried to resurrect the innings with a quick stand of 75 runs but Ashwin removed the latter before lunch to make matters worse for the visitors.
Shami (2/33 in 12 overs) bowled with a lot of fire during the session while Umesh Yadav's (3/32 in 11 overs) third wicket of the innings primarily belongs to Saha, who once again proved why he is rated as the best Test wicketkeeper in the world.
On a pitch where Indian batsmen looked at ease, it was an every moment struggle for the Proteas.
Shami was getting the semi new-ball to dart back in after pitching while Yadav was primarily bowling outswingers.
Nightwatchman Anrich Nortje (4) was uncomfortable from the start as Virat Kohli set an attacking field that included four slips and a gully.Shami got deliveries to rear up from the length and one such delivery was awkwardly fended by Nortje and skipper Kohli at fourth slip took a smart catch diving to his right.
Theunis de Bruyn (30) hit a couple of cover drives but it was a moment of inspiration from Saha that brought about his end.
Trying an expansive drive off Yadav, De Bruyn's hard flash was flying towards first slip and Saha plucked it off in thin air, leaving South Africa tottering at 53 for five.
However Du Plessis and De Kock batted positively punishing the loose balls and didn't look in much trouble like the earlier batsmen.
Du Plessis had 10 hits to the fence, including one maximum while De Kock hit seven boundaries.
It was Ashwin, who removed De Kock with a classical off-break that pitched on the middle and the southpaw was squared up and beaten trying to play for the turn only to find the the bails clipped.
In the post lunch session, spinners took control as Senuran Muthsamy (7) shouldered arms to a delivery from Jadeja that turned back sharply and was adjudged leg-before.
Ashwin finally got rid of Du Plessis with a delivery that straightened as he played for turn and the leading edge was taken by Ajinkya Rahane at first slip.
Vernon Philander (23 batting) and Keshav Maharaj (21 batting) then put up a resistance for more than 18 overs in an unbroken 35-run stand for the ninth wicket.