VVS Laxman and Mahendra Singh Dhoni scored centuries as India moved into a position of immense strength on the third day of the second Test against South Africa at the Eden Gardens.
Laxman oozed class and style en route to an unbeaten 143, his 15th Test century, and Dhoni played his part in a massive seventh-wicket partnership with 132 not out as India ground home the advantage.
The home side eventually declared on 643-6, a lead of 347 and South Africa faced the prospect of a tricky 10 overs to stumps.
Bad light, however, ended play early and South Africa closed on six for no loss from the five deliveries that were possible.
India began another profitable day with a belligerent show from nightwatchman Amit Mishra (28), although shoddy fielding from the tourists aided India's cause considerably.
Laxman started briskly, turning Dale Steyn for consecutive boundaries in the first over and driving Paul Harris delectably through the covers, but it was Mishra's innings which proved frustrating for the visitors.
Mishra resumed his innings by advancing down the track and carting the left-arm spinner for a boundary over long-on and was then dropped almost immediately later, Jacques Kallis grassing a chance at first slip.
Mishra, who slashed Kallis for two boundaries in three deliveries in an over, was reprieved again on 25 by Graeme Smith and went on to add three more to his score before Morne Morkel eventually struck with the second new ball, Kallis completing the dismissal with an excellent catch at second slip.
South Africa's bowling attack stuck to their task admirably in overcast conditions in the morning, but was let down by further lapses in the field.
Dhoni was a little tentative initially and the Proteas missed at least two good chances at Laxman's scalp before he breached the half-century mark.
Steyn flicked the inside-edge as the batsman mistimed a drive, but the ball flew over the stumps and barely eluded a diving AB de Villiers, South Africa's stand-in wicketkeeper.
Another offering was put down by JP Duminy when the batsman was on 48 and Laxman went past the half-century mark even as Smith spread the field.
The home side went into the lunch interval at 431-6, but the afternoon session was particularly pleasing for India's supporters as Dhoni and Laxman consolidated the home side's position by amassing 117 runs without surrendering a wicket.
India's last recognised batting pair were again cautious at the start of the final session and Laxman was stuck for sometime on 99 before he eventually reached his fourth Test century in nine matches at Eden Gardens. He averages more the 91 at this venue.
Dhoni then reached his fourth century and first against South Africa off 155 deliveries, making it only the second time four Indian batsmen have achieved centuries in the same innings.
Both batsmen then climbed into South Africa's weary attack as they extended the lead beyond the 300-run mark, Dhoni clobbering of Duminy for consecutive sixes in an over before the declaration was made.