New Zealand are just one win away from clinching a 10th Sevens World Series title in 13 years after the first day of the final leg of the championship in London.
New Zealand came into the tournament with an 11-point lead at the top of the standings over second-placed Fiji.
They routed Russia 49-7 in their opening match, with Tomasi Cama and Frank Halai, both nominated for the IRB Sevens Player of the Year award, scoring two tries each.
New Zealand then saw off Kenya 24-nil but had to come from 10-nil down at halftime against Argentina in their final pool match for a 15-10 win secured by three unanswered second half tries from captain DJ Forbes, Mark Jackman and Joe Webber.
Victory over defending London champions South Africa in the quarter-finals tomorrow will give New Zealand an unassailable lead at the top of the table.
Fiji, Australia and Samoa are the other teams with 100 per cent records heading into the last eight, the Samoans defeating hosts England 14-7 in the final match of Saturday's play.
The remaining quarter-finals see Fiji facing England and Australia playing Argentina.
The big story of day one though, was that Spain, minnows in the 15-a-side game but an emerging force in this format, also advanced to the quarter-finals.
Spain stunned Wales 22-7 and beat Zimbabwe 38-nil.
These results, allied to a respectable 19-5 loss to Fiji, saw Spain qualify as Pool C runners-up for their first appearance in the Cup quarter-finals of an IRB Sevens event where they will face Samoa tommorow.