The Blitzboks got off to a winning start on Day One of the Cape Town Sevens when they beat Samoa in their first match on Saturday.
The defending World Sevens Series champions scored 22 points to Samoa's 12 after leading 10-7 at the break.
Samoa got on the scoreboard first and took a 7-0 lead, but a yellow card to Alatasi Tupou for a high tackle gifted the Blitzboks the chance to take a three-point advantage at the break.
Neil Powell's men scored two more tries in the second half, before Samoa ran in a consolation try at the very end.
The Blitzboks will take on Zimbabwe at 3.48pm before meeting Dubai champions New Zealand in their last match on Day One at 7.56pm.
Tries: Kyle Brown, Philip Snyman, Justin Geduld, Impi Visser
Tries: David Afamasaga, John Vaili
Conversions: Alatasi Tupou
African News Agency (ANA)