A fiery spell from South Africa paceman Dale Steyn sent India hurtling towards a heavy defeat on the third day of the first Test in Nagpur.
Steyn claimed wickets on either side of a dazzling century from Virender Sehwag (109), who shared a 136-run fourth-wicket stand with debutant Subramaniam Badrinath (56). The fast bowler finished with seven for 51 as India was bowled out for a measly 233 in the first innings.
With a sizeable lead of 325, the visitors enforced the follow-on and tightened the screw by removing both openers cheaply, leaving India with a mountain to climb.
At stumps, the home side had stumbled to 66-2, still needing 259 to make South Africa bat again.
Sachin Tendulkar was 15 not out with Murali Vijay unbeaten on 27 at the close.
Morne Morkel had produced the first breakthrough of the morning before Steyn stepped up to leave India reeling at 56-3 inside the first half-hour.
Morkel, who provided admirable support to Steyn throughout the day, induced Gautam Gambhir (12) into a defensive shot with his first delivery of the morning, the opener flicking an edge to Mark Boucher.
The inexperienced Vijay, occupying the injured Rahul Dravid's regular No.3 slot, was Steyn's first victim, the batsman embarrassingly bowled for four while shouldering arms.
Steyn then saw off Tendulkar cheaply, luring the batsman into a drive on seven and securing the edge which went straight through to Boucher.
Sehwag had watched partners come and go from the other end, but eventually found an able ally in Badrinath and the duo began restoring the innings.
Sehwag had begun in positive fashion, but the fall of wickets forced him into a more cautious approach.
However, he showed the bald surface was still good for batting as he interspersed good running between the wickets with boundaries.
He reached his 18th Test century with a single off Jacques Kallis, his stay laced with 13 fours and adding a touch of respectability to India's total.
Sehwag was well entrenched when he threw away his wicket.
The opener had already hit consecutive boundaries in a Wayne Parnell over which yielded 13 in four deliveries, but chased a ball pitched well outside off stump and spooned a catch to JP Duminy at deep cover.
Badrinath, who held up one end in a determined and vigilant manner, slowly closed in on a maiden half-century, eventually reaching the milestone with a nicely-driven boundary through the covers off Morkel.
He was joined by Mahendra Singh Dhoni following Sehwag's dismissal and India took tea in a relatively decent position at 221-4.
However, Dhoni's dismissal for six in the first over of the final session sparked a dramatic and spectacular collapse.
Left-arm spinner Paul Harris scalped Dhoni with one that pitched in the rough outside leg stump, spun viciously across the batsman and brushed the gloves on its way to Kallis at slip.
Steyn then accounted for Badrinath in the next over, the batsman lazily flicking a full-length delivery straight to Ashwell Prince at mid-wicket.
The fast bowler then ran through the tail, adding the wickets of debutant Wriddhiman Saha (nought), Zaheer Khan (two), Amit Mishra (nought) and Harbhajan Singh (eight) to his name.
Graeme Smith enforced the follow-on and Morkel again dismissed Gambhir, the opener bowled for one while shouldering arms to a delivery that swung in.
Steyn then picked up his eighth wicket of the day, Sehwag (16) slashing at a delivery and edging to Smith at first slip.
The only sour note for South Africa was a back injury to Boucher, forcing the wicketkeeper to stay off the field during India's second innings.