Kenya surprised by reaching the Cup quarter-finals of the Cape Town Sevens and South Africa and New Zealand bounced back from defeats to qualify.
Kenya will join the top seeds in the Cup quarter-finals after finishing with two wins and a draw while hosts and defending champions South Africa beat England 10-0 in the final match of the day to book their place in the last eight.
Juan de Jongh began proceedings before Ryno Benjamin confirmed the win in the second half to the delight of the home crowd with the Blitzboks a defeat away from missing out on the Cup competition for the first time since the 2013 Hong Kong Sevens, having earlier lost to Kenya 14-12 who remained unbeaten heading into Sunday.
Neil Powell's side will face Australia in a repeat of last week's Plate final in the quarters, while last week's runners-up England will play in the Bowl on day two, their first appearance in that competition since the 2013 Port Elizabeth Sevens, after suffering defeat to South Africa and drawing to Kenya 19-19 in their opening match.
Elsewhere, series leaders Fiji and Australia were the only sides to win all three of their matches at a sold-out Cape Town Stadium, with the second round of the Sevens World Series throwing up lots of thrills and spills in front of 55,000 fans.
For Ben Ryan's side, who scored 129 points and 21 tries, their three pool wins means they have won 33 of their last 33 pool matches with London 2014 the last time they suffered defeat, to Australia 24-12. The Dubai champions will play France on day two in Cape Town after the les Bleus qualified on points scored following a 26-26 draw with Canada in their final match of Day 1.
New Zealand suffered defeat to Canada for only the second time in history but Sir Gordon Tietjens' side bounced back to top Pool D with a 19-10 win over Samoa to set up a quarter-final with Argentina.
The USA, who missed out on top spot in their pool by giving away a penalty with the scores tied against Australia and allowing 18-year-old and debutant Henry Hutchinson to claim the win for Scott Bowen's side, will play Kenya – Mike Friday set to come head to head with his former side.
Cape Town Sevens quarter-finals: Sunday, December 13
(kick-off times are local, GMT +2)
Kenya v USA – 13:10
New Zealand v Argentina – 12:48
Australia v South Africa – 12:26
Fiji v France – 12:04
England v Portugal – 11:42
Canada v Russia – 11:20
Wales v Zimbabwe – 10:58
Scotland v Samoa – 10:36
Pool A: Fiji, Argentina, Scotland, Russia
Fiji 34-19 Scotland
Argentina 33-5 Russia
Fiji 52-0 Russia
Argentina 19-14 Scotland
Scotland 33-10 Russia
Fiji 43-0 Argentina
Pool B: England, South Africa, Kenya, Zimbabwe
England 19-19 Kenya
South Africa 26-5 Zimbabwe
England 43-0 Zimbabwe
South Africa 12-14 Kenya
Kenya 34-0 Zimbabwe
South Africa 10-0 England
Pool C: USA, Australia, Wales, Portugal
USA 26-19 Wales
Australia 45-0 Portugal
USA 52-7 Portugal
Australia 21-14 Wales
Wales 40-5 Portugal
USA 21-26 Australia
Pool D: New Zealand, Samoa, France, Canada
New Zealand 19-14 France
Samoa 24-10 Canada
New Zealand 12-24 Canada
Samoa 19-22 France
France 26-26 Canada
New Zealand 19-10 Samoa
With thanks to World Rugby