The team was reduced to 14 players after just two minutes when halfback Iritana Hohaia was sent off for an accidental head clash. That forced some serious readjustments in the backline, with No 10 Rosie Kelly moving in one position, though she is no stranger to the role.
The Black Ferns were further briefly reduced to 13 players with a late first half yellow card on Liana Mikaele-Tu’u.
In between those incidents, the USA harassed and harried the Black Ferns with some fierce, aggressive defence which forced handling errors and missed tackles from the normally slick Rugby World Cup holders.
Despite having lost both their Pacific Four matches by wide margins, the USA ripped into its work, scoring tries to blindside flanker Paluvava’u Freda Tafuna from a lineout and No 8 Rachel Johnson, who drove over from close range. There was a yellow card on USA No 7 Georgie Perris-Redding for another accidental high tackle, but the referee Julianne Zussman ruled there was a mitigating factor, as Perris-Redding was the second player into the tackle.
The sole joy for the Black Ferns in the first stanza came from a try by debutante hooker Grace Gago from a lineout drive in which Kendra Reynolds delivered the last pass.
At 17-5 to the USA at oranges, it was going to need some personnel and subtle tactical changes along with better discipline for the Black Ferns to reel off a 15th straight victory to mark the first game as captain for lock Maia Roos, the youngest woman to ever lead the team.
That all came to pass. The injection of some older, wiser heads and the Black Ferns going more direct in the pack allowed their offloading game to flourish and saw the team run in five tries and an impressive 34 unanswered points, even with a player down.
A trysaving tackle on the line by Reynolds seemed to galvanise the Black Ferns and was matched not long afterwards by a thunderous hit from Kennedy Simon.
Replacement halfback Arihiana Marino-Tauhinu was first to score, off a Kelsey Teneti break, then Pip Love who, along with Tanya Kalounivale stiffened the scrum, scored in close after a lineout. The Black Ferns took the lead for the first time at 57 minutes.
No 8 Mikaele-Tu’u bulldozed over the defence off a lineout, while Ruahei Demant, who pulled all the right strings with her calm leadership and authoritative play, and won the player of the day going for just over 45 minutes’ work, scored on the blind, busting the line.
The final exclamation point on a compelling second half effort came with a late try to centre Amy du Plessis in the corner.
The players now return to their Farah Palmer Cup teams before reconvening for the second O’Reilly Cup match against the Australian Wallaroos on September 30 in Hamilton.
Black Ferns 39 (Grace Gago, Arihiana Marino-Tauhinu, Pip Love, Liana Mikaele-Tu’u, Ruahei Demant, Amy du Plessis tries; Renée Holmes 3 con, pen) USA 17 (Paluvava’u Freda Tafuna, Rachel Johnson tries; McKenzie Hawkins 2 con, pen) HT: 17-5 USA