Durban:Graeme Swann and Stuart Broad took England to the brink of victory as South Africa collapsed on the fourth day of the second Test at Kingsmead on Tuesday.
South Africa, trailing by 232 runs on the first innings, were 76 for six when bad light gave the home team a reprieve until the final day on Wednesday. The hosts will resume needing 156 to avoid an innings defeat.
Off-spinner Swann and fast bowler Broad took three wickets each as South Africa's top six batsmen were blown away in less than an hour of play on either side of tea.
There were no signs of a potential batting collapse earlier in the day when England took their first innings total to 575 for nine declared, with Ian Bell hitting 141.
England's batsmen had virtually no problems against the South African bowlers on an easy-paced pitch but it seemed a different game when Swann and Broad got to work.
Ashwell Prince and South African captain Graeme Smith had taken South Africa's second innings total to 27 without any major alarms before Swann was brought on to bowl the tenth over.
Swann continued his uncanny knack of taking a wicket in his first over of an innings when he dismissed Prince with his second ball, caught by Bell off bat and pad at silly-mid-off.
He followed up two overs later by bowling Hashim Amla in the last over before tea when the batsman missed a drive against a ball which spun back sharply.
There was a shock for South Africa six balls after tea when Jacques Kallis padded up to a ball from Broad which cut back and hit the top of his off stump.
Astonishingly, AB de Villiers also elected to pad up to Broad four overs later, with the ball again cutting back and flicking his front pad. Given out leg before wicket by umpire Amish Saheba, he asked for a television review but the decision was upheld.
JP Duminy was bowled by the next ball when he tried to withdraw his bat from a lifting delivery and played the ball onto his stumps.
With the floodlights on and the light deteriorating Smith was sixth out when he played around a ball from Swann and was given out leg before by umpire Aleem Dar. He too sought a review without success.
Mark Boucher and Morne Morkel survived until bad light ended play with 16 overs remaining.
Earlier, Bell and Matt Prior (60) put on 112 for the sixth wicket in a partnership which wrecked South African hopes of making a breakthrough early in the day.
They had no difficulty in seeing off Dale Steyn and Morne Morkel, South Africa's main strike bowlers, at the start of play and Smith was soon forced on the defensive.
Bell and Prior gradually increased the tempo and Prior seemed set to go on a major assault when he raised a 77-ball half-century with a six off left-arm spin bowler Paul Harris. He hit one more boundary but was then bowled by off-spinner JP Duminy when he chopped an attempted cut onto his stumps.
Bell, whose place as a number six batsmen had been questioned because it left England with only four specialist bowlers, justified the confidence shown in him by the team management with a composed, confident innings.
After posting his fifty off 65 balls on Monday, Bell was more circumspect on Tuesday, reaching his ninth Test century off 172 deliveries when he went down the pitch and lofted Harris over mid-on for his eighth four. He also hit a six.
It was Bell's first Test century since he made 199 against South Africa at Lord's in July 2008.
England went on the attack immediately after lunch, adding 62 runs for the loss of three wickets in nine overs before Andrew Strauss declared.
England batsman Paul Collingwood, who made 91 on Monday, dislocated his left index finger during fielding practice before play. He was sent for X-rays which revealed no fracture. He did not field at the start of the South African second innings.