The Blitzboks were slow out of the blocks in the Estadio Ciudad de Malaga; they were put on the back foot by the physical approach of Scotland and some ill-discipline in their own ranks. This resulted in JC Pretorius being yellow carded after not rolling away from a tackle four minutes in, on their own tryline.
The Scots kept the ball for a number of phases and with South Africa a man down, the numerical advantage worked in their favour, with Paddy Kelly dotting down and Gavin Lowe converting for a 7-0 lead, which was also the only score in the first half.
The second half saw the Blitzboks going to work.
Scotland's restart went out on the full, handing South Africa a free kick on the halfway line. An inch-perfect pass by Selvyn Davids found Zain Davids on a brilliant angle, and the prop ran 50 meters to score.
The try prompted more brilliance from the Blitzboks, with Selvyn Davids the real playmaker. He scored twice in two minutes, with one of his five-pointers from a brilliant chip-and-chase.
That eased the Blitzboks into a 17-7 lead, but they were far from finished. Siviwe Soyizwapi scored in the corner after a mazy run by Pretorius, but the SA captain injured his shoulder in scoring his 13th try of the season.
Replacement prop Christie Grobbelaar scored the fifth and final try of the match after a strong run down the line.
Blitzbok coach Neil Powell said the opening half was not the best they had, mainly due to ill-discipline.
"Scotland were always going to be a tough opponent first up and when we conceded four penalties and a yellow card in that first half, we did make it harder for ourselves," said Powell.
"The message before the match was exactly that - we should not underestimate the Scots. They are a strong and traditional rugby power and will always test you. We were also mindful of the fact that we have not seen them play for almost two years."
The second half effort was more true to form, admitted Powell: "Credit to the guys, they came back very well in the second half. We took early control and maintained that for the remainder of the game.
"We scored five tries and Scotland never got out of their own half, so that was a pretty rewarding effort in the second half and I am very happy with that," the coach added.
The Blitzboks will return to the field at 14h17 (SA time) on Saturday when they face England in their second pool match.
South Africa 27 (0) - Tries: Zain Davids, Selvyn Davids (2), Siviwe Soyizwapi, Christie Grobbelaar. Conversion: Branco du Preez.
Scotland 7 (7) - Try: Paddy Kelly. Conversion: Gavin Lowe.