Calvert said it was a physical game and keeper Megan O'Connor suffered a concussion after a collision but should be fine for next week.
O'Connor along with Candice Armstrong were standouts for the Whanganui side, Calvert said.
"[Armstrong] just ran all day, ran herself into the ground. They showed really good leadership and showed how much it means to them to get three points."
Whanganui had a goal disallowed before halftime and forced a few saves out of Moturoa's keeper.
"We just need to be a little bit more streetwise," Calvert said.
"When you lose all the time it becomes second nature."
Calvert said Rose Davidson impressed after being left out of the previous game and with a few players away he was able to blood a couple of debutantes.
The second of the season's three rounds begins next Sunday when Whanganui host Massey University at Wembley Park at 2.45pm.
Massey beat Whanganui 2-0 in the opening game of the season and now lead the league with three wins.
Whanganui then travel to Taradale and New Plymouth Girls' High School without another home fixture until the end of June.
In Sunday's other match Massey drew 2-2 with New Plymouth Girls' High School.