Hong Kong - The Springbok Sevens team easily won their two Pool E matches on Saturday against Hong Kong and Wales to advance to the quarter-finals of the Hong Kong Sevens.
South Africa will face Fiji in the last eight on Sunday, the third and final day of the tournament.
New Zealand play Portugal, Samoa are up against Australia, and Russia, who reached the Cup quarter-finals for the first time, take on England.
Two tries from Paul Delport and Sibusiso Sithole and one for Sevens debutant Tshotsho Mbovane ensured South Africa topped Pool E at the end of day one after a 42-12 victory against Wales.
Earlier, the US Sevens champions inflicted defeat on Hong Kong as they ran out eventual 45-0 winners against the hosts. Cecil Afrika and Chris Dry both scored two tries.
On Friday the Blitzbokke had beaten Spain 33-5 in their opening fixture of the tournament, the fifth stop of the HSBC Sevens World Series.
"I'm really pleased with the overall effort today, especially our display against Wales," Treu said.
"The real business only starts tomorrow (Sunday) morning in the quarter-finals and our aim will be to keep our focus and our composure and to keep the momentum.
"I'm also very glad that Tshotsho Mbovane could score his first try in his first tournament.
"This is a special tournament and he will remember it for a long time."
With 24 teams in the draw for the tournament split across six pools, only the winner in each group will be guaranteed a place in the Cup quarter-finals on the third and final day.
They will be joined in the last eight by the two best runners-up.
Group results from the Hong Kong Sevens on Saturday:
Pool A
France 40 South Korea 7
New Zealand 19 Portugal 12
Portugal 41 South Korea 14
New Zealand 19 France 7
Pool B
USA 36 China 14
England 33 Japan 14
Japan 17 China 12
England 37 USA 12
Pool C
Scotland 40 Mexico 7
Samoa 24 Tonga 17
Tonga 41 Mexico 0
Samoa 31 Scotland 14
Pool D
Kenya 45 Malaysia 12
Fiji 29 Russia 14
Russia 50 Malaysia 0
Fiji 40 Kenya 0
Pool E
Wales 28 Spain 5
South Africa 45 Hong Kong 0
Spain 24 Hong Kong 7
South Africa 42 Wales 12
Pool F
Argentina 21 Zimbabwe 12
Australia 26 Canada 24
Canada 24 Zimbabwe 10
Australia 21 Argentina 14
South Africa will face Fiji in the last eight on Sunday, the third and final day of the tournament.
New Zealand play Portugal, Samoa are up against Australia, and Russia, who reached the Cup quarter-finals for the first time, take on England.
Two tries from Paul Delport and Sibusiso Sithole and one for Sevens debutant Tshotsho Mbovane ensured South Africa topped Pool E at the end of day one after a 42-12 victory against Wales.
Earlier, the US Sevens champions inflicted defeat on Hong Kong as they ran out eventual 45-0 winners against the hosts. Cecil Afrika and Chris Dry both scored two tries.
On Friday the Blitzbokke had beaten Spain 33-5 in their opening fixture of the tournament, the fifth stop of the HSBC Sevens World Series.
"I'm really pleased with the overall effort today, especially our display against Wales," Treu said.
"The real business only starts tomorrow (Sunday) morning in the quarter-finals and our aim will be to keep our focus and our composure and to keep the momentum.
"I'm also very glad that Tshotsho Mbovane could score his first try in his first tournament.
"This is a special tournament and he will remember it for a long time."
With 24 teams in the draw for the tournament split across six pools, only the winner in each group will be guaranteed a place in the Cup quarter-finals on the third and final day.
They will be joined in the last eight by the two best runners-up.
Group results from the Hong Kong Sevens on Saturday:
Pool A
France 40 South Korea 7
New Zealand 19 Portugal 12
Portugal 41 South Korea 14
New Zealand 19 France 7
Pool B
USA 36 China 14
England 33 Japan 14
Japan 17 China 12
England 37 USA 12
Pool C
Scotland 40 Mexico 7
Samoa 24 Tonga 17
Tonga 41 Mexico 0
Samoa 31 Scotland 14
Pool D
Kenya 45 Malaysia 12
Fiji 29 Russia 14
Russia 50 Malaysia 0
Fiji 40 Kenya 0
Pool E
Wales 28 Spain 5
South Africa 45 Hong Kong 0
Spain 24 Hong Kong 7
South Africa 42 Wales 12
Pool F
Argentina 21 Zimbabwe 12
Australia 26 Canada 24
Canada 24 Zimbabwe 10
Australia 21 Argentina 14