The ten-point win sets Simon Amor's team on the right track and they will be well-aware of the importance of going as far as possible in Hong Kong with just a few rounds remaining after this one.
Heading into Hong Kong, USA sit top of the standings, closely followed by Rugby World Cup Sevens 2018 winners New Zealand and Olympic Champions Fiji who are seeking their fifth successive title in Hong Kong.
The Pool C match between the old rivals started with a minute's silence to commemorate the victims of the Christchurch shootings.
In Pool A, South Africa beat Japan 22-7 and Samoa defeated Scotland 17-7, while France routed Portugal 40-7 and Argentina beat Canada 19-14 in Pool B.More news: SEC says Tesla CEO should face substantial fines
The Philippine Volcanoes men's rugby team pulled off a big upset against Zimbabwe, 24-12, on Saturday in a do-or-die match to reach the quarterfinals of the World Series Qualifiers in Hong Kong Saturday.
Rodrigo Freudenthal and Rodrigo Marta had tries for the invitational Portuguese side.
In other matches, Samoa beat Scotland 17-7, South Africa defeated Japan 22-7, England beat Wales 36-19, US defeated Spain 36-7 and New Zealand thrashed Australia 40-19.
Canadian speedster Justin Douglas celebrated his 25th birthday with the 130th try of his career, but it wasn't enough for Canada to beat Argentina in their opening match on Friday at the Hong Kong Sevens.More news: United States media report says all of Pakistans F-16s intact; IAF rebuts
Overall leaders the United States and second-placed New Zealand both recorded victories as the World Rugby Sevens Series event in Hong Kong began today.
Tournament victor will qualify for next season's Women World Sevens Series as a core team.More news: House committee chairman warns of subpoenas in White House security clearance probe