India claimed the final four South African wickets late in the afternoon session to bowl out the hosts for 373 - giving themselves a 41-run lead at stumps on day three of the final Test in Cape Town.
Mark Boucher scored a valuable half-century down the order but Anil Kumble dismissed Dale Steyn and Makhaya Ntini in successive balls to wrap up the South African effort.
Boucher was superb and patiently dispatched any poor deliveries to the boundary, his 50 coming off 96 balls, including six fours.
However, he was out when he edged a Munaf Patel ball to Dinesh Karthik behind the stumps just five minutes and three balls after reaching the milestone, without adding any further runs.
That was a hammer blow to South Africa's chances of posting a first-innings lead and India quickly mopped up the tail.
Debutant Paul Harris showed similar application with the bat to that seen in his bowling and stoically repelled the Indian attack, ably supporting Boucher.
Harris was 11 not out off 29 balls and struck two fours in his composed knock.
Resuming after tea on 283 for six, Boucher and Shaun Pollock added 69 runs for the seventh wicket before the latter perished chasing a wide ball from Zaheer Khan.
Pollock made a useful 31 from 57 balls and batted for 88 minutes.
His dismissal was followed by Boucher's, before Kumble bowled Steyn (one) and followed that up next ball when he trapped Ntini leg before wicket for a duck.
Earlier, India started the day by fighting back on the third morning, grabbing the wickets of both overnight batsmen, Graeme Smith and Hashim Amla.
Resuming on 144 for one, Smith took up where he left off on day two and cracked Zaheer for consecutive fours through mid-on.
Kumble opened the bowling from the Kelvin Grove End in an effort to exploit an appreciably big area of rough that had opened up outside the left-hander's off-stump.
India's plan worked and Kumble had Smith caught at silly mid-on by a diving Virender Sehwag.
The Proteas captain played well for his highest score of the series - 94 off 141 balls - but will feel that he missed out on an opportunity to make a bigger mark on a gloriously sunny day in Cape Town.
India struck again four overs later when Amla edged a Shanthakumaran Sreesanth delivery to wicketkeeper Karthik for 63.
Jacques Kallis came in and played cautiously before finding his range and producing a number of classy shots to the boundary off Patel.
Kallis remained unbeaten at the lunch break on 18, along with Cape Town local Ashwell Prince on nine not out.
In the afternoon session, the pair resumed and shared an 83-run partnership before Sachin Tendulkar snared the crucial wicket of Kallis for 54 - his 41st Test half-century.
One wicket soon became two when Prince followed an over later, playing back to a wide delivery from Kumble and only succeeding in dragging the ball onto his leg stump for 26.
And a third wicket of the session, Herschelle Gibbs, three balls before tea further unsettled the Proteas and they were now firmly on the back foot on 283 for six.
Gibbs was unlucky to be given out to a dubious bat-pad catch off Kumble's bowling for seven.
India now go into the fourth day with a handy lead and in a strong position to push on and post a big total on a deteriorating pitch.
