|First Test, Johannesburg (day four, stumps)|
|India 280 & 421 v South Africa 244 and 138-2|
South Africa face a world-record run chase if they are to avoid defeat to India on the final day in Johannesburg.
The hosts closed on 138-2 in pursuit of 458 for victory in the first of a two-test series.
Alviro Petersen will resume on 76, alongside Faf du Plessis (10), after Graeme Smith was run out for 44.
Cheteshwar Pujara scored 153 for India, while Virat Kohli's 96 meant he failed to become the fourth Indian batsman to hit two centuries in the same Test.
South Africa's target is 40 runs more than the record run chase, which was achieved by West Indies in a 2003 victory over Australia.
India, who have already won a series in the Caribbean this year, built on their overnight position of 284-2 to reach 421.
Pujara and Kholi were both caught by AB de Villiers off the bowling of Jacques Kallis and Jean-Paul Duminy respectively, before India's tail-end failed to fire.
An unbeaten 29 by Zaheer Khan was their only meaningful contribution to follow, before South Africa were back at the crease mid-way through the second session.
Smith and Alviro Petersen put on their first 100-run stand in more than a year, before the former was run out when mid-on fielder, Ajinkya Rahane scored a direct hit.
Hashim Amla (4) was dismissed without offering a stroke for the second time in the match when he ducked, only to see Mohammed Shami's delivery stay low and find off-stump.
There was history made late in the day when MS Dhoni brought himself on to bowl two overs, making this the first test in which both wicketkeepers have taken the ball after AB de Villiers did likewise in India's second innings.
The second Test will begin on Boxing Day, with South Africa bowler Morne Morkel a doubt with an ankle ligament injury.