The Blitzboks defended well at times in both games and used their attacking opportunities to seal the wins. They scored eight and conceded three tries, two of which game after the buzzer in their two matches.
South Africa scored five tries in their 31-7 victory over Spain, and even though the scoreline doesn't tell the story, they were forced to defend at times during the game, which they did very well to keep the tricky Spanish out until they crossed after the hooter had sounded.
Selvyn Davids scored the first try one minute in when he showed great speed from the back of an attacking scrum just outside the Spanish 22.
Dewald Human converted to make it 7-0, and then he scored the second try a few minutes later after a string of penalties against Spain.
The last penalty was close to Spain's own tryline and Human didn't need a second invitation to tap and crash over for the try to stretch the Blitzboks' lead to 12-0.
Spain finished the half strong but the Blitzboks' defence held firm in their own 22 to take their 12-point lead into the break.
From the restart, Christie Grobbelaar set off on a strong run, but he was stopped just short. A few phases later though, Impi Visser found space and scored the Blitzboks' third try, with Human adding the extras to make it 19-0.
Tristan Leyds then made it 26-0 after a great steal on the ground by Visser, who fed the speedster to race away for the try, which was converted by Selvyn Davids.
Rosko Specman celebrated the start of his 35th tournament in style when he grabbed the Blitzboks' fifth try from a clever grubber to make it 31-0.
Spain grabbed a consolation try after the buzzer, but the Blitzboks had done what they needed by then.
The match against Samoa was a typical arm-wrestle, with the physical islanders scoring first after four minutes.
To add insult to injury, Human hobbled off with an injury, with Leyds replacing him.
A minute later, Quewin Nortje showed some real pace to go over on the left, but the conversion was not over and the scores were tied at 5-5, which is how it stayed until the break.
The Blitzboks started the second half with a bang when Selvyn Davids went over from a set play from an attacking lineout, which was set up by a brilliant penalty clearance kick from Leyds, who moved play from the SA to the Smaoan 22.
Two minutes later, Shilton van Wyk made it 15-5 with another try from a set play, but again the conversion was unsuccessful.
With 90 seconds to go, Specman was shown a harsh yellow card for a deliberate knock-on, but the Blitzboks held firm until they ran out of defensive numbers after the hooter, which allowed Samoa to score their second try.
"Our first goal for the tournament was to focus on the game against Spain and then take the next one as it comes, so we're on the right track at the moment and it was good to wrap up day one with two from two," said Siviwe Soyizwapi, who made his first appearance of the season after months on the sidelines with an injury.
"You'll always feel nervous coming back from a long spell on the sidelines, but as soon as I made that first contact , it was all guns blazing from there. I really enjoyed being out there today, and taking in each and every moment."
The Blitzboks face France in their final pool game at 08h24 (SA time) on Saturday, and Soyizwapi warned his team-mates to be mindful of the European side: "They are really playing well at the moment, they finished well in the last tournament and brought good momentum here.
"We weren't perfect and will have to work on a few things in our own game, even though we went two from two, so we'll have to analyse the French team for when we face them first thing tomorrow morning."
Scorers:
South Africa 31 (12) Spain 7 (9)
SA - Tries: Selvyn Davids, Dewald Human, Impi Visser, Tristan Leyds, Rosko Specman. Conversions: Human (2), Selvyn Davids.
Spain - Try: Enrique Bolinches. Conversion: Juan Martinez.
South Africa 15 (5) Samoa 10 (5)
SA - Tries: Selvyn Davids, Quewin Nortje, Shilton van Wyk.
Samoa - Tries: Uaina Tui Sione, Daniel Patelesio.