The All Blacks Sevens battled to a tense 12-5 victory after trailing initially and hanging on grimly inside their 22 in the final passage of play.
Argentina immediately kicked the ball deep inside All Blacks Sevens territory. A turnover and a penalty amplified pressure and eventually New Zealand cracked when Matias Osadcuzk flipped the ball from behind his back to an unmarked German Schulz.
New Zealand led 7-5 at halftime. Space was at a premium so Ngarohi McGarvey-Black threw a swirling 25-metre pass which found Sione Molia free on the edge. Molia attracted multiple defenders and turned inside to Scott Curry who finished.
Moses Leo was injured in the first half, but would deliver the telling blow. Caged inside their 22, Molia attempted a change in tactics with a clearance kick. It was charged down by a wall of Pumas but Leo collected the rebound and beat three defenders in dashing 80-metres clear, despite juggling the ball and having to change direction to avoid the last chaser.
Captain Sam Dickson was abrasive on defence but took himself and Australian referee Jordan Way out in an unfortunate collision with three and a half minutes remaining.
New Zealand didn’t receive much love from the replacement official but sturdy tackling from McGarvey-Black, Scott Curry and Tone Ng Shiu particularly was enough to defy the stubborn Pumas
Argentina knocked the ball five-metres out from the line seeking a match-levelling try. The Pumas team was fourth in the World Series, their best ever position.
New Zealand will play Ireland in the semifinals at 10:35pm after the Irish shocked hosts South Africa 24-14. The brilliant Jordan Conroy scored two tries to boost his tally to 104 in 106 matches.
World Series winners Australia defeated France 14-5 in their quarter final to set up a clash with 2005 world champions Fiji who eliminated Samoa 21-10.
The Black Ferns Sevens whitewashed Ireland 28-0, but the scoreline doesn’t reflect how hard victory was to earn.
New Zealand only led 7-0 at halftime and were sloppy throughout, hassled by the determined Irish. It was largely individual brilliance separating the two countries.
Niall Williams' left-foot step cracked open the defence after two minutes, New Zealand pilfering the kick-off and a Michaela Blyde break creating front-foot momentum.
New Zealand had to wait almost an entire half for their next breakthrough. Williams outnumbered three on two, ten-metres out from her own line, found Porita Woodman thundering inwards on a sharp angle and the champion busted 90-metres for a classic.
Shiray Kaka injected much needed enthusiasm and flare from the bench. Her pass freed Alena Sail who cleared out over 40-metres and then Kaka went 60-metres by herself.
Captain Sarah Hirini and Risi Pouri-Lane were relentless on defence with the latter winning two clean turnovers and adding four conversions too.
The Black Ferns play France in a replay of the Olympic final in the semis at 10:07pm. France beat Fiji 21-14 in their quarter final with Joanna Grisez scoring a 70-metre runaway with the last play.
In the other semi-final Commonwealth Games and World Series champions Australia will play USA. Australia knocked out England 35-5 and the USA edged Canada 10-7 in the quarter finals.
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