Rugby Sevens: Understrength Black Ferns Sevens off to winning start against Great Britain at Dubai

An understrength Black Ferns Sevens outfit have opened their account with victory at the latest world series stop in Dubai.

Missing some of the stars of the recent Rugby World Cup 15s event - Sarah Hirini, Portia Woodman, Stacey Fluhler, Ruby Tui and Theresa Fitzpatrick - the NZ women were drawn against Great Britain in their opening pool encounter and emerged 19-12 winners.

Tries to Michaela Blyde and Shiray Kaka - both converted by skipper Tyla Nathan-Wong - put them clear early, and while the British struck back with two tries, Niall Williams sealed the win with a third touchdown.

"Coming off the bench, I knew I had to come out and make an impact," said Williams.

"We've got three players who could potentially debut this weekend," said Williams. "I made my debut here 6-7 years ago, so this is the best one to do that."

New Zealand face Brazil later Friday night (NZ time), with France looming early Saturday morning.

Meanwhile, after crashing to ninth at Hong Kong last month, the All Black Sevens have stumbled again in their Dubai opener, falling 31-28 to Argentina.

Joe Webber gave New Zealand the early advantage, but the contest went try for try, until Argentina scored either side of halftime to seize momentum. 

The NZ men responded, through Moses Leo, but a dropped pass in their own 22, allowed Argentina to build a 10-point advantage. Brady Rush ran the length of the field to cut the deficit, but their desperate bid to snatch a last-ditch victory fell short. 

They probably need to overcome archrivals Fiji to progress out of their pool into quarter-finals.