The City star scored two goals as Japan flaunted their high quality style of football in their first game following the Women’s World Cup.
Mina Tanaka put Japan in front after just two minutes before Hasegawa doubled their lead from the penalty spot.
While Argentina struggled to have consistent spells of possession, Japan continued to threaten goalkeeper Vanina Correa’s goal.
Hana Takahashi added her name to the scoresheet in the 25th minute before Hasegawa netted her second, Japan’s fourth, shortly before half-time.
Japan showed no signs of slowing down for the second 45 minutes with Kiko Seike and Hina Sugita netting a goal each within five minutes of each other.
Even in a friendly, Japan were relentless with their rotated squad. A handful of their Japan-based representatives are with a different Japanese national team that will be competing in the Asian Games over the coming weeks.
Japan finished the friendly in emphatic fashion. Riko Ueki became their sixth different goal scorer as she netted her spot kick with 10 minutes left to play.
Seike made it 8-0 in injury time to finalise the thrilling win.
Elsewhere, Khadija ‘Bunny’ Shaw led the line for Jamaica in their CONCACAF Women’s Championship 2-0 defeat to Canada.
Shaw and Jamaica will return to action on Wednesday 27 September in the reverse fixture with Canada, with kick-off scheduled for 00:00 (UK).