The Blitzboks have one of the easier pool draws at the Hong Kong Sevens, but the near-fright against Japan on Friday will stand them in good stead for a possible quarter-final against USA or England.
The South Africans were trailing 7-5 at halftime, and an upset reminiscent of the 2015 Rugby World Cup opening game was on the cards.
But the Vancouver Sevens winners found some of their rhythm in the second half to register a 22-7 victory.
They have bigger fish to fry in the shape of Scotland (5.41am SA time) and Samoa (9.22am) on Saturday, but coach Neil Powell was not too perturbed about the performance against Japan.
“To have things not going your way in the first match is also not that bad, as we needed to work hard to grab the match back from Japan,” he said.