South Africa 162 (Hamza 62, Yadav 3-40, Jadeja 2-19) and 132 for 8 (De Bruyn 30, Shami 3-10, Yadav 2-35) trail India 497 for 9 dec by 203 runs

India need two wickets to complete a whitewash over South Africa but they will have to wait until Tuesday morning to do it. The visitors might have one more night in India, awaiting a fate that was writ from the second innings in Visakhapatnam, when Mohammed Shami ripped through their middle order and showed how much of a role seam bowlers would play in this series.

Though R Ashwin remains on top the wicket charts, it was Shami and Umesh Yadav who exposed a weakness South Africa would not have dreamed they had, especially not in the subcontinent.

South Africa have been surprised by short balls, beaten by pace and caught off guard by bowlers who attack the stumps, the very same thing they have seen their own attack do, season after season. But this is the season of change and India have spent the series showing how much they have evolved. No longer a team that relies on conditions loaded in the spinners' favour, they are now an outfit that wins away and that is not only happy to compete on fair-minded surfaces, but can dominate on them.

Sixteen South African wickets fell on day three as they were made to follow-on in consecutive Tests for the first time since 2002, and seven of their players were dismissed twice on the same day. A concussion substitute was required for the third time in Test history after Dean Elgar ducked into a Yadav short ball and was struck just above the ear. Theunis de Bruyn replaced him and was the top-scorer in the second innings, scant consolation after being dropped and watching his replacement make a strong enough case to stay in the No.3 spot for the foreseeable future.

If there's positive South Africa could take, it was Zubayr Hamza's first-innings effort. After watching his captain Faf du Plessis get beaten and bowled by a Yadav beauty that swerved away from him in the first over of the day, Hamza played a sprightly knock. He was confident on the front foot, energetic in his approach and was the perfect foil for Temba Bavuma, who was circumspect but promised so much. Hamza and Bavuma put on a fourth-wicket stand of 91, but once Hamza was dismissed, the procession began.

Ravindra Jadeja had Hamza caught on the back foot, when the batsman was shaping for a flick, but was beaten in the end. This, immediately after an unsuccessful review from India. In the next over, Bavuma came down the track to defend against debutant Shahbaz Nadeem but the ball turned away from him and into Wriddhiman Saha's gloves. Bavuma was stumped for 32, a score which only added to his failure to covert starts. The tail wagged a little in the form of George Linde but India were all over South Africa. The visitors lost 7 for 55, getting dismissed for their lowest total of the series.

With weather threatening to reduce the time left in the match, and South Africa so far behind, both in terms of runs and in their states of mind, Virat Kohli had no second thoughts about enforcing the follow-on. And within ten overs it was obvious he had made the right decision.

South Africa were reduced to 26 for 4 when the blow to Elgar resulted in early tea. By then, Quinton de Kock had played down the wrong line to Yadav, Hamza was late on a ball that straightened from Shami, du Plessis took an unnecessary review when he was given out lbw off Shami, and Bavuma was out for a duck.

Shami showed South Africa how it's done once again. Hit the deck hard. Use the short ball aggressively. Keep the lines tight. The only thing he didn't do was finish South Africa off. Not even Ashwin managed that. The South African tail has routinely frustrated India and this time Anrich Nortje hung on with de Bruyn till stumps. However, it's only a matter of time before India complete the formalities.