Fast bowlers Vernon Philander and Dale Steyn shared nine wickets as Sri Lanka again struggled in South Africa to be bowled out for 180 on day one of the first test.
The Proteas were then 90-1 in their first innings at close of play at SuperSport Park to take firm control of the series opener despite captain Graeme Smith's dismissal for 61 in the second-last over of the day.
Sri Lanka has never won a test in South Africa - losing six of its seven previous matches - and was immediately under pressure in its first series in the country in nine years when Philander and Steyn combined on a bouncy, seaming surface after the host won an important toss and put the tourists in.
Philander continued his remarkable start in test cricket with 5-53, his third five-wicket haul in three matches, and top-ranked test bowler Steyn became the second-quickest man to 250 wickets as he took 4-18.
"There was a bit of assistance out there and that's what I tried to explore. Subcontinent teams obviously fear a green top," Philander said.
Sri Lanka, on a 14-match winless streak in tests, managed two half-century partnerships on an initially tricky pitch to recover to 156-4 after early trouble at 12-2.
But bustling right-arm seamer Philander took two wickets in two balls - and three in the afternoon session - to snuff out the promising fightback and Steyn ripped out the tail to end Sri Lanka's innings just before tea. Legspinner Imran Tahir returned 1-22 and the only wicket to fall to a slow bowler on the opening day.
Veteran batsman Thilan Samaraweera (36) had anchored the second of Sri Lanka's fighting stands - having not been in the initial squad for the tour - to lift the tourists' spirits.
He combined for 65 runs with topscorer Angelo Mathews (38) after lunch as Sri Lanka's middle order responded to a perilous position at 91-4 by counterattacking with a flurry of boundaries. Samaraweera hit five fours and Mathews struck six and they added 50 off 59 balls in 48 minutes.
But Samaraweera's dismissal began Sri Lanka's slide as it suddenly lost 6-24 in five overs under Philander and Steyn's afternoon onslaught, with the pace pair bullying the batsmen and justifying Smith's decision to put the tourists in.
"We always knew if we could get No. 7 and 8 in there we had a chance of bowling them out cheaply," Philander said. "Anything under 200, we'll take it."
The Proteas also have much to prove in the three tests against Sri Lanka having not won a home series since 2008, and having let strong positions slip in draws against Australia, India and England.
Smith and fellow opener Jacques Rudolph (27 not out) cemented South Africa's advantage with an 88-run opening partnership as the pitch eased for batsmen, but Sri Lanka had a glimpse of hope when Smith was out lbw to Dilhara Fernando (1-21) just before stumps.
The South Africa skipper had taken charge of the partnership with seven boundaries in his half-century before he missed a straight one from Fernando seven balls from the close.
"The last few overs we bowled really well and took Graeme Smith's wicket," Sri Lanka wicketkeeper Kaushal Silva said. "Tomorrow we need to start all over again, just forget about what happened today and just think about the positives we can do tomorrow. That's all we can do.
"The bowlers they've got and the wicket they gave us was a hard task for us."
Having picked up the wickets of No. 1 test batsman Kumar Sangakkara and opener Tharanga Paranavitana in the morning, Philander removed Samaraweera and Silva off successive balls in a key spell in the middle of the day on his way to his third five-wicket haul.
He has taken 19 wickets in five innings over three matches and was the first South African to take five in an innings in each of his first three tests.
Samaraweera went to a faint edge behind and Silva gloved down the legside to Mark Boucher first ball. Both decisions were given out after video reviews by South Africa.
Philander had Mathews caught at slip off a fizzing, head-high delivery for his fifth wicket, and Steyn clean bowled tailenders Chanaka Welegedara and Dilhara Fernando - also off successive balls - to end the innings and ensure the Proteas cashed in on the helpful early conditions.
Steyn's first wicket, that of Sri Lanka captain Tillakaratne Dilshan, took him to 250 wickets in his 49th test - one match more than former Australia great Dennis Lillee.
Samaraweera, Mathews, opener Paranavitana (32) and Mahela Jayawardene (30) had all got starts for Sri Lanka, but couldn't launch prolonged attacks as South Africa wrestled control.
