Shanthakumaran Sreesanth produced another inspired spell of bowling to keep India on course for victory in the first Test against South Africa.
He followed his five-wicket haul in the first innings with 3-47 as the home side struggled to 163-5 at the end of day three, chasing a target of 402.
But he could not remove Ashwell Prince, who was 54 not out at the close.
India made 236 earlier in the day after a stand of 70 between VVS Laxman (73) and Zaheer Khan (37).
The tourists, who have never won a Test on South African soil, managed to add 80 to their overnight score despite losing Mahendra Dhoni and Anil Kumble early, with Shaun Pollock and Andre Nel the successful bowlers.
"If we don't win we shouldn't get back to the dressing room"
Khan hit two sixes off home skipper Smith, whose three overs of off-spin cost 26, but he and Laxman were finally separated when Makhaya Ntini had Laxman caught at first slip.
Ntini found the edge of Khan's bat two balls later and keeper Mark Boucher making no mistake behind the stumps, but there was still time a late flourish from the tail.
After surviving a Nel bouncer, Sreesanth lofted the next delivery for a straight six and ran down the pitch towards the bowler twirling his bat in celebration.
Last man VRV Singh followed up with two boundaries off Ntini before he was run out for 11 to bring the innings to an end.
The day had begun badly for South Africa because of controversy surrounding star batsman Jacques Kallis.
The Sunday Times newspaper published the text of an e-mail allegedly sent by Kallis to a member of the public, who questioned why he does not sing the national anthem before international matches.
Their run chase also got off to a difficult start when Herschelle Gibbs fell to Khan's fourth delivery, which was angled across him - his second duck of the match.
And India remained on top throughout the afternoon as Sreesanth and the other Indian bowlers produced a tireless effort to pick up the wickets of Smith and Hashim Amla.
Smith (10) sliced a ball from Sreesanth to point, where Virender Sehwag took an excellent diving catch, and Amla (17) could do no more with a superb leg-cutter than edge it to the keeper.
Kallis looked solid in making 27 but was out-thought by Sreesanth who followed up a short delivery with one pitched up to a full length outside of stump, tempting him into a drive which resulted in a catch to Sourav Ganguly at third slip.
South Africa could not afford the run out of AB de Villiers (17), who attempted a quick single after playing the ball down the ground but was beaten by Khan's underarm throw as he ran around from in from mid-on.
Sreesanth and the slip cordon were convinced they had Prince on 44 after another magnificent ball from Sreesanth ended up in the gloves of keeper Dhoni, but the umpire decided there had been no edge.
Prince eventually reached his fifty off 136 balls as he and Boucher added 43 for the sixth wicket before the close.
But Boucher was fortunate in the final over of play as Sreesanth fizzed a sharply rising ball past the outside edge and then tempted him into a hook shot which landed just inches away from Khan at deep backward square leg.