Harmer's six-for hands India their biggest Test defeat and seals South Africa's 2-0 sweep

In front of empty stands in India's newest Test venue, South Africa competed their utter domination of the hosts with a whitewash and their heaviest Test defeat in terms of runs. More than just the order of session breaks was turned upside down in India's eastern-most Test ground where South Africa sealed their first series win in India in 25 years and India's second series defeat in 12 months after 12 years of spotless record.

Simon Harmer out-bowled by miles the home spinners in a country, whose ordinary tour in 2015 resulted in a seven-year hiatus for him in Test cricket. No one has now taken more wickets at a better average in a series in India than his 17 wickets at 8.94. Marco Jansen was a little behind with 12 at 10.08, but he ended the series with yet another thing about which we can say: "only Marco could have done that". A sensational catch over the shoulder, running back, diving and taking it one-handed. Just the kind of wicket Harmer won't mind being denied a maiden 10-for by.

This was the farthest result on India's minds when Shubman Gill joked after losing yet another toss in Kolkata that it seems he will win only in the World Test Championship (WTC) final. Since then, India lost Gill to injury three balls into his work, and then both the Tests to leave themselves a hill to climb if they want to entertain thoughts of the WTC final. They now have 48.15% points halfway into their league matches. Historically at least 60% has been needed to get through to the final.

The defending champions, who had to deal with some elitist sniggering about their schedule in the last cycle, now have 75% of their points. Temba Bavuma, the captain who brought home the mace, was still undefeated in Tests after 12 matches at the helm.

That Bavuma wouldn't lose this one had been clear halfway into this Test. Since then, South Africa played India out ruthlessly and started the fifth day needing eight wickets to take the full 12 WTC points from this match. This classic Indian Test pitch was now offering consistent turn and natural variation.

So a combination of Harmer and Jansen, who took a five-for and a 93 in the first innings, was always going to test India's resolve to bat the day out. The overnight batters, B Sai Sudharsan and nightwatch Kuldeep Yadav, enjoyed some luck with one wicket denied by a no-ball and another by a drop at slip by Aiden Markram, who took five catches in the first innings.

The luck ended around half an hour into the day. It had always looked a matter of time against Harmer's guile and persistence. Kuldeep was the first one to go, bowled by an offbreak that didn't turn. You can't quite make an offbreak not turn, but you can give it every chance to do so by changing the seam orientation, which Harmer did.

In the same over, Harmer completed the brace of dream dismissals for an offspinner. He had bowled KL Rahul through the gate on the fourth evening; now he took Dhruv Jurel's outside edge with drift and less turn than expected.

Rishabh Pant is often criticised for taking too many risks, but this innings provided a counterpoint. Against a really slow offbreak from Harmer, Pant was a sitting duck the moment he decided to offer a forward-defensive. The extra bounce took the catch to Markram at slip, who was now moving rapidly towards the world record for most catches in a match.

Sai Sudharsan enjoyed another dropped catch as he and Ravindra Jadeja took India into tea. Sai Sudharsan's luck ran out in the first over after the break with Harmer getting a rest having bowled through the entire first session. He defended a Senuram Muthusamy half-volley. It didn't turn, and Markram took another catch.

Adequately rested, Harmer came back from the other end than the one that had been giving him wickets and took out Washington Sundar and Nitish Kumar Reddy in quick succession. With a softer ball now, he started to bowl quicker and took the edge from Washington with a 90kmph offbreak. Markram took a sharp catch to go past Ajinkya Rahane's world record of eight in a match.

The right-hand batters were always going to struggle more now with three dismissals in play: bowled through the gate, outside edge and bat-pad catches. Reddy introduced the glove on the reverse sweep to give Harmer his best match figures, making him South Africa's most successful bowler in India and the most prolific South Africa bowler after 14 Tests.

Jadeja was the one India batter who swept well from the length that had other batters in trouble. He scored a consolatory half-century, read the room and shelved his sword celebrations, and was stumped when trying to take Keshav Maharaj on.

The final moment, fittingly, belonged to Jansen. He scored quick runs when India were in control of South Africa's scoring in the first innings, when it seemed no one could dominate the bowling. His long levers, which made this possible, also created the wicket of Yashasvi Jaiswal in the first innings, then India's only half-centurion. Then he unleashed bouncers when the pitch was still flat, taking more wickets with bouncers than anyone has taken in an innings in India.

By the time South Africa bowled the second time around, the pitch offered consistent turn and didn't call out for a superhuman effort from Jansen. Then again, why deny us when you can nonchalantly take an impossible catch to end the match and the series? Lest we forget.