The defending champions scored two second half tries to stretch their 6-3 halftime lead to 18-3, and Nienaber was frank about the fact that although it was a hard match, it was a positive start for the defending champions.
“It was a slippery one,” said Nienaber. “Scotland are ranked fifth in the world, and we could see how they pushed against France in their warm-up games, so we knew it would be a grind.
“The historical winning margin between the teams is 15 points and it was the same today. They are a tough team who get stuck in, so it was always going to be a tough battle.
“That said, this is the first step in the right direction. It’s going to be difficult to get out of our pool, so our only focus right now is on Romania.”
With Scotland being limited to only one penalty goal for their efforts in the hot and humid Marseille conditions, Nienaber praised the effort by his charges in that department.
“Defence is beautiful for me,” said Nienaber. “All credit to Scotland. They play with great speed and innovation on attack, so we had to be really sharp to cut out their options.
“The players worked very hard off and on the field this past week to keep them at bay.”
Commenting on the effective Springbok scrum, captain Siya Kolisi said: “It was quite clear we didn’t start the way we normally start, and at half time we agreed that we should be better because the set pieces are very important for us.”
On the injury front Nienaber revealed that lock Eben Etzebeth had suffered a shoulder injury, but he said they would only know the extent of the injury following a thorough medical assessment.
The Springboks will face Romania in their second pool match in Bordeaux on Sunday, 17 September.