Ravichandran Ashwin rips through South Africa

The 29-year-old off-spinner plundered seven wickets as India thrashed South Africa inside three days to secure an unassailable 2-0 series lead.

The hosts sewed up the series with a match to spare by taking by far the greater advantage of a cracked pitch that had looked days worn even at this third Test's opening.

Ashwin dismissed South Africa's last four batsmen for just 21 runs as the visitors slumped from 32 for two in their second innings at the start of the day to 185 all out.

Amit Mishra swiped the other three wickets as spin again took total control, with South Africa losing a series on the road for the first time since their 2-0 defeat to Sri Lanka in 2006.

Ashwin rightly won the man-of-the-match plaudits for his 12-wicket haul, but the overarching influence of the pitch must not be understated.

Opener Murali Vijay set an unwanted record, his first-innings knock of 40 becoming India's lowest-ever high score in a Test match victory.

The hosts were nevertheless far more concerned with ending South Africa's 16-match unbeaten streak on the road.

India started the day scenting Virat Kohli's first home win as Test skipper, and were hardly likely to be denied once Ashwin and Mishra ripped into South Africa's middle order.

Dean Elgar mustered 18 before being snared leg before by Ashwin, with AB de Villiers suffering the exact same fate.

Hashim Amla and Faf du Plessis then halted the slide at 58 for four, only for both men to depart in the space of two overs after pushing the visitors' tally into three figures.

Mishra removed both men for 39 runs apiece, Amla departing first, caught by Kohli, before Du Plessis was clean-bowled.

Ashwin trapped JP Duminy for 19 at 164 for seven - and that started the final wicket glut that sealed the deal.

Dane Vilas was caught behind for 12, before Kagiso Rabada holed out to Kohli for six.

And when Morne Morkel had his stumps breached on just four runs, India completed both their third Test victory and series triumph.