In the eighth minute, Team USA opened their account through Alyssa Parker's field goal.
With just a point to their name from the promising stalemate against Vantage Black Sticks on day one, the Americans' desperation was there for all to see.
Enter Jill Witmer in the 13th minute, doing justice to Erin Matson's penalty-corner service by rifling the ball into the backboard with a thud for a 2-0 lead.
In the 25th minute Kathleen Sharkey did all the hard work and even got the ball around goalkeeper Megumi Kageyama but, regrettably, none of her teammates were in the D to help push it into the net as the Japanese cavalry arrived to avert more disaster.
No goals were scored in the second 15-minute spell.
At the 40-minute mark, Japan found themselves too deep in retreat mode in the trenches after a concerted effort again saw Michelle Vittese high-fiving all the way back to her half after putting USA up 3-0 with a field goal.
The dismantling continued in the final quarter when, after consecutive penalty-corners, captain Melissa Gonzalez slipped the ball past Kageyama after a well-timed feed from Alyssa Manley to make it 4-0.
Japan struck back with a field goal the very next minute from Yukari Mano to pull it back to 4-1 but it's fair to assume captain Hazuki Yuda and her troops would have taken little consolation from their overall effort.
Katelyn Falgowski said communication was definitely a work in progress for USA.
"It's about putting it all together at once," said Falgowski, revealing they had taken a mindset of treating the game as a quarterfinal.
"You know, earlier on in the tournament it may not go your way but the quarterfinal match is what really matters."
She paid tribute to the USA defence as well to negate Japan's imposing threat as a great counterattacking side.
Falgowski said they planned to carry on what they started today when they face New Zealand from 5pm on Saturday.
Talking through translator Satomi Yamaguchi, of Napier, a poker-faced Yuda said Japan had to make leaps and bounds against Australia on Saturday from 3pm.
"We couldn't play our game today," she said, adding they were caught out of position too often.
A delighted Yamaguchi, who turned 52 yesterday, received a Japan team dress shirt as a birthday gift from the team.