Tomasi Cama scored a second-half try to rally series leaders New Zealand past England 12-7 and into a semi-final against South Africa at the IRB Rugby Sevens World Series.

The South Africans, defending USA Sevens champions, routed Argentina 24-5 to keep their repeat hopes alive in the fifth of nine rounds of the global series.

Fiji, which trails New Zealand 73-70 in the season points championship, booked a berth in the last four with a 12-5 victory over Wales. Setefano Cakau scored two second-half tries to rally Fiji from a 5-0 half-time deficit.

The Fijians advanced to a semi-final against rival Samoa, which downed Kenya 19-14 in the other quarter-final thanks in part to a hat trick from Alafoti Faosiliva.

New Zealand, nine-time World Series champions, have not won the US leg since the 2008 edition in San Diego but they took a major step by ousting England, which stands third in the season points chase, nine adrift.

New Zealand's Frank Halai opened the scoring with a try 36 seconds into the quarter-final match, but England answered with a Dan Norton try and Marcus Watson's conversion kick gave the English a 7-5 edge at half-time.

Cama scored the deciding try and kicked the conversion, the second time in the day he had done so to rally New Zealand to victory.

New Zealand completed an unbeaten Pool A run with a 12-5 victory over Samoa, rallying after a Paul Perez try put the Samoans up 5-0 after only 77 seconds.

D.J. Forbes pulled New Zealand level at half-time and Cama's try and conversion kick early in the second half provided the winning margin.

England was forced to face New Zealand after settling for second in Pool D following a 7-7 draw with Kenya that left the African side atop the group on tie-breakers.

Lavin Asego's try and conversion put Kenya ahead 7-0 at half-time but Tom Mitchell scored 1:47 into the second half with Kenya's Oscar Ouma in the Sin Bin and Marcus Watson's conversion left England deadlocked.

Steven Hunt, Cecil Afrika, Kyle Brown and Branco du Preez scored tries in South Africa's quarter-final triumph, while Diego Palma kept the South American side from being blanked with a try in the last seconds.