Fiji topped Pool A of the Hong Kong 7s after beating Argentina 26-19 in its final match at the So Kon Po Stadium on Saturday.
The Ben Gollings coached side will now meet South Africa in the third Cup quarterfinal at 2.28pm tomorrow.
New Zealand will face Argentina in the first quarterfinal at 2.02pm, France will battle against Spain at 2.25pm while the USA and the Great Britain will play in the last Cup quarterfinal at 3.11pm.
