|Fourth Test, Delhi, day five|
|India 334 & 267-5 dec: Rahane 100*, Morkel 3-51|
|South Africa 121 & 143: De Villiers 43, Ashwin 5-61|
|India won by 337 runs; won series 3-0|
India overcame stubborn resistance from South Africa to win the fourth and final Test in Delhi by 337 runs and seal a 3-0 series victory.
Resuming on 72-2 on the final day in pursuit of a notional 481, the tourists were bowled out shortly after tea for 143, made in 143.1 overs.
Hashim Amla fell early for 25 off 244 balls and AB de Villiers 43 off 297.
The tourists lost their last five wickets for seven runs after tea as Ravichandran Ashwin claimed 5-61.
It was the off-spinner's fourth five-wicket haul of a series in which he took 31 wickets at an average of only 11.12.
|1st Test, Mohali: India won by 108 runs|
|2nd Test, Bangalore: Draw|
|3rd Test, Nagpur: India won by 124 runs|
|4th Test, Delhi: India won by 337 runs|
However, the 29-year-old was made to work harder than at any stage during the series by a defiant South Africa, the world's number one-ranked Test side.
They were led by an uncharacteristically defensive display from De Villiers, who holds the records for the fastest fifty, century and 150 in one-day internationals.
Between them, Ashwin and India's three other frontline bowlers delivered 136.1 overs, 87 of which were maidens.
Ravindra Jadeja took 2-26 off 46 overs, including 17 consecutive maidens, Umesh Yadav claimed 3-9 off 21 and Ishant Sharma conceded only 23 runs from 20 overs.
Much of that time was spent trying to dislodge De Villiers, who was unbeaten on 11 overnight and carried on where he left off during a 345-minute stay at the crease.
After captain Amla was bowled by a wonderful delivery from Jadeja that turned to hit off stump, De Villiers was assisted by Faf du Plessis, who took 53 balls to score his first run and had made 10 from 117 when he was lbw to the slow left-armer.
De Villiers lost JP Duminy before tea - lbw to Ashwin without scoring - and Dane Vilas after the interval, bowled by Yadav for 13 off 57 deliveries.
The crucial breakthrough, though, came moments later when Ashwin found turn and bounce to have De Villiers taken at leg slip off his glove.
It was the second wicket to fall in the space of 27 balls as India ran through the tail, Ashwin sealing victory by bowling Morne Morkel.