South Africa made light work of taking the five wickets they needed on the final day of the first Test as Sri Lanka succumbed to a 206-run defeat at St George's Park.
The tourists came into Friday's play 240-5, still 248 runs away from an unlikely victory target but any hopes they had of even salvaging a draw were soon extinguished as they crumbled to 281 all out.
Overnight batsmen Angelo Mathews (59) and Dhananjaya de Silva (22) were the first two men to fall, both lbw to Kyle Abbott, and when Rangana Herath perished to Vernon Philander, Sri Lanka had lost three wickets inside eight overs.
Kagiso Rabada accounted for Dushmantha Chameera and a resounding victory was wrapped up when Keshav Maharaj cleaned up Nuwan Pradeep (4) as South Africa completed the job in just 13.3 overs of play.
Captain Mathews added only one run to his tally before Abbott (2-38) pinned him in front, the decision upheld on review, and Dhananjaya followed in the same fashion - also sending the decision upstairs to no avail.
Philander (1-65) held a fine caught-and-bowled chance to get rid of Herath (3), diving forward to take it in his left hand and Rabada (3-77) induced a glove behind to oust Chameera for a duck.
Maharaj (3-86) had the final say, bowling Pradeep with a beauty that pitched on middle and leg and struck off stump as the Proteas secured a 1-0 lead in the three-match series, the next instalment of which begins in Cape Town on Monday.