South Africa cantered past Argentina 35-17 to win the Cardiff IRB Sevens title at the Arms Park .
With traditional heavyweights New Zealand, Fiji, England and Samoa cast aside in the past two days, the surprise finalists made the most of their rare chance at Sevens glory.
Argentina were brave in defeat, but had no answer to the rugged defence and pace out wide of the South Africans, who knocked out Fiji and England on the way to the crown.
Tries to Conrad Jantjes, Fabian Juries and Marius Schoeman, all from long range and all under the posts, gave the Springboks a daunting 21-5 lead at the break.
Argentina hit back with a double to Matias Albina, but the Chester Williams-coached South Africans shrugged off the interruption of a male streaker to score through replacement Rudi Coetzee and secure the title.
In the battle for the minor trophies, crowd favourites Georgia beat Italy 24-12 to win the Shield, burly winger Roland Reid continued his fine form to lead Scotland to a 35-14 win over France in the Bowl final, and New Zealand dispatched neighbours Australia 36-14 to win the Plate.
The win gives New Zealand 100 series points - 12 more than England with only next week's London event left on the calendar.
Even if England win their home event and secure 20 points, the Gordon Tietjens-coached Kiwis will need to only make the Cup semi-finals to secure their fourth straight IRB world title. Even if they were again knocked out at the quarter-final stage, a win in the Plate section could see them win the title on points difference.
England coach Joe Lydon admitted: "I'd say the overall title is gone - I can't see New Zealand slipping up again."
His captain Simon Amor added: "We've never won our home tournament and we're desperate to get our hands on the trophy.
"We're only thinking of that - the overall title will work itself out."
Bowl quarter-finals: France 17 Portugal 5, Canada 31 Italy 0, Scotland 26 Georgia 12, Russia 34 Spain 0.
Cup quarter-finals: England 14 New Zealand 10, South Africa 17 Fiji 5, Samoa 22 Australia 7, Wales 21 Argentina 12.
Shield semi-finals: Italy 17 Portugal 14, Georgia 21 Spain 10.
Bowl semi-finals: France 24 Canada 5, Scotland 19 Russia 12.
Plate semi-finals: New Zealand 35 Fiji 0, Australia 27 Wales 10.
Cup semi-finals: South Africa 22 England 10, Argentina 15 Samoa 0.
Shield Final: Georgia 24 Italy 12.
Bowl Final: Scotland 35 France 14.
Plate Final: New Zealand 36 Australia 14.
Cup Final: South Africa 35 (tries - C Jantjes, F Juries 2, M Schoeman, R Coetzee; cons - J Van Schalkwyk 5) beat Argentina 17 (tries - F Martin Aramburu, M Albina 2; con - D Villen).
2003 Cardiff IRB Sevens champions: South Africa.
Cardiff tournament points: South Africa 20, Argentina 16, England 12, Samoa 12, New Zealand 8, Australia 6, Fiji 4, Wales 4, Scotland 2.
Overall IRB Sevens Championship points: New Zealand 100, England 88, Fiji 78, South Africa 70, Australia 58, Samoa 56, Argentina 36. Others: Wales 8, Scotland 5.
Next and final leg: Twickenham, London, June 6-7.