Hosts England started strongly, beating Fiji and Samoa in their opening two matches, but lost to Argentina 26-17 in the final match of the day. Despite the loss they ended day one as Pool C winners and second seeds to set up a quarter-final against Glasgow Sevens champions South Africa.
In the other two Cup quarter-finals Kenya meet Fiji and Australia, the Pool A winners meet USA.
In the core team qualifier, Portugal were the only side to win all three of their matches and face Georgia on day two. France, Wales, Canada and Samoa will compete in the Bowl competition.
New Zealand v Argentina Kenya v Fiji Australia v United States
England v South Africa
POOL A (RSA, USA, AUS, FRA)
Results: Australia 35-12 FranceSouth Africa 12-19 USA USA 15-19 Australia South Africa 17-14 France South Africa 5-0 Australia USA 19-17 France
Australia beat France 35-12 to bounce back from an opening 5-0 defeat to South Africa and head into the Cup quarter finals as Pool A winners. In their second match Peter Schuster finished wonderfully to give Australia a 19-15 victory against USA despite a hat-trick from Brett Thompson who finished second.
Cecil Afrika snatched a dramatic late 17-14 victory for last weekend's Cup champions South Africa against France as Frankie Horne marked his 50th consecutive Series tournament on day one.
Vincent Deniau scored the opening try of the match and Terry Bouhraoua scored twice for France in their first match with USA, but the Tokyo and Glasgow Sevens Plate winners won 19-17.
POOL B (NZL, WAL, CAN, KEN)
Results: Wales 17-14 Canada New Zealand31-17 Kenya New Zealand 24-7 Canada Kenya 31-19 Wales New Zealand 45-5 Wales
The 11-time Series champions New Zealand beat Canada 24-7 in their opening match having trailed 7-0, and also came from 17-0 behind to defeat Kenya 31-17 with Kurt Baker and David Raikuna scoring twice each.
Humphrey Kayanage returned to the Kenyan squad for the London Sevens and scored one of the tries of the day, running the entire length of the pitch, as his side beat Wales 31-19.
The reigning Rugby World Cup Sevens champions held on to a narrow 17-14 victory against Canada thanks to Adam Thomas' late try and a try-saving tackle from Alex Walker in their second match.
POOL C (ENG, ARG, FIJ, SAM)
Results:Argentina 0-24 Fiji England 34-7 SamoaEngland 27-0 Fiji Argentina 10-7 Samoa Fiji 33-7 Samoa Argentina 26-19 England
Dan Norton scored England's 1000th point of the Series as Ben Ryan's side continued to impress on day one with a 34-7 defeat of Samoa. Norton scored their second hat-trick of the day after Jeff Williams crossed three times as the hosts defeated Fiji 27-0 in their opening match but ended their home tournament with a 26-17 loss to Argentina.
Facundo Panceyra Garrido scored with the last play of Los Pumas' match to beat Samoa 10-7, but were unable to repeat that against Fiji who beat them 24-0. Samoa's day ended disappointingly too with a 33-7 defeat to Pacific neighbours with Samisoni Viriviri scoring twice.
Alongside the main competition an eight-team tournament is taking place from which three will gain core team status for the 2013/14 HSBC Sevens World Series.
All eight sides will enter the quarter finals on day two, but their matches on day one will determine their seeding for day two. Hong Kong beat Georgia 17-12 in their second match while Scotland won both of their opening matches against Georgia and Zimbabwe.
Spain bounced back from a 19-17 defeat to Tonga to beat Russia 19-14, while the Pacific Islanders narrowly lost their second match 12-7 to Portugal.
In the quarter-finals, Portugal will face Georgia, Spain meet Hong Kong, Zimbabwe await Rugby World Cup Sevens hosts Russia and last week's hosts play Tonga. The four winners will progress to the semis from which three sides will gain promotion to the Series.
With thanks to the IRB