The 26-year-old was at her brilliant best in midfield, playing a central role in the fourth goal when she laid on for Jun Endo to fire home.
With Spain cruising to a 3-0 victory on Friday, it was crucial that the 2011 World Cup winners got off to a strong start in Group C.
And they were in control from the get-go, with Aoba Fujino forcing a fine reaction save from Catherine Musonda just after the 10-minute mark to set the tone in Hamilton.
The Japanese, and Fujino, went even closer soon after when she tried her luck from distance, but her stinging drive came crashing back off the post with Zambia’s goalkeeper at full stretch.
As we’ve seen time and again at the Academy Stadium, Hasegawa was crucial to that strong start, dictating the tempo of the play from the middle of the park.
Japan even had the ball in the net just after 20 minutes when Mina Tanaka pounced on a loose ball from a set piece, but a VAR review spotted an offside in the buildup to keep the scores level.
Musonda was tested from distance once again as half-time approached, and was equal to Fuka Nagano’s deflected effort, after she’d been teed up by Hasegawa with a clever cutback.
But the stopper could do nothing to prevent the opener just ahead of the break, with a clever lofted ball down the right by Hasegawa unlocking the Zambia defence and releasing Fujino, who squared for Hinata Miyazawa to tap home.
Tanaka thought she’d doubled the advantage soon after the restart when she fired home on the turn inside the area, but the forward was denied by the offside flag once again.
Japan were awarded a penalty moments later when Fujino was brought down by the onrushing Musonda after she’d been released in behind by Hasegawa, but a VAR review once again handed Zambia a lifeline.
Number two would follow early in the second half, with the City midfielder instrumental in the move.
Afforded too much time in the middle of the park, Hasegawa clipped a clever ball in behind the Zambia defence, with Tanaka finding the far corner on the slide from the eventual left wing cross.
It should’ve been three soon after when Fujino skied an effort when one on one with the goalkeeper, but Miyazawa would extend the lead on the hour when she stole in between a Zambia defender and Musonda to tap Tanaka’s cutback home from close range.
Hasegawa would grab an assist with around 15 to play, releasing Jun Endo down the left and allowing the midfielder to grab a fourth with a clinical finish back across goal.
It was just rewards for the City midfielder, who had been one of Japan’s standout performers throughout proceedings in Hamilton.
There was still time for a fifth for the 2011 champions, with Musonda given her marching orders when she brought down Riko Ueki inside the area at the death.
The forward dusted herself down and did the honours at the second time of asking after smashing her initial effort against the bar before a retake due to encroachment by substitute goalkeeper Eunice Sakala.
Hasegawa and co. are back in action on Wednesday 26 July when they face Costa Rica in their second Group C clash.
