Alexia Putellas in action for Spain as they beat Zambia 5-0 to qualify for the last 16 of the Women s World Cup (AFP)
Hermoso marked her 100th appearance for Spain with a brace while the fit-again Alexia Putellas was handed a start and helped make the opening goal for Teresa Abelleira.
Spain's big win in Auckland came after they beat Costa Rica 3-0 in their opening game, and this result also saw secured a last-16 spot for Japan.
The two sides are locked on six points atop Group C, but Spain have a better goal difference and so just need a draw to finish in first place when they clash in Wellington on Monday.
"We haven't seen the best version of Spain, that is absolutely clear," said Vilda after the game at Eden Park which also confirmed Zambia's elimination.
"We have four days to improve, recover physically and mentally, and put in a better performance against Japan."
Vilda was unhappy that his team -- one of the favourites to win the World Cup -- switched off after racing into a two-goal lead early on, before turning on the style again towards the end.
"After the second goal we took our foot off the pedal and that is something we need to correct. We can't settle for this," he said.
There were plenty of positives, though, not least Hermoso's performance on a landmark night for her.
"The setting could not be better, getting to 100 matches, and to be able to celebrate it here with another victory in a World Cup is a reason to be happy," she said.
- Putellas handed start -
Reigning Ballon d'Or Putellas, who recently returned from over nine months out with a serious knee injury, was taken off at half-time, with Vilda looking to preserve his star player for the group decider.
Used off the bench against Costa Rica, here she came in from kick-off, one of six Barcelona players in the starting line-up.
Spain went ahead in the ninth minute when Hermoso laid off a Putellas pass for Real Madrid midfielder Abelleira to blast high into the net from outside the area.
It was 2-0 on 13 minutes as Putellas flighted a ball up from the left side of the box to the back post where Hermoso headed in.
Zambia, with the lively Barbra Banda leading the attack, had the majority of the crowd of almost 21,000 behind them but struggled to create chances.
Putellas was cruising through the game, finding pockets of space in an inside-left role, but she did not reappear for the second half as Vilda made three half-time changes.
Her place was taken by Redondo and the Levante forward got the third on 69 minutes, getting in front of Agness Musesa before rounding goalkeeper Eunice Sakala to score.
The fourth arrived 60 seconds later, Hermoso converting the rebound after Irene Guerrero hit the post, although the goal was initially ruled out for offside before being given after a VAR check.
Hermoso was denied a hat-trick when she saw a shot tipped onto the bar by Sakala, but Redondo got her second with five minutes left as she controlled Eva Navarro's cross before slotting in.
Again the flag came up for offside, but again the decision was overturned on review.
That made it a second straight 5-0 hammering for Zambia after their defeat against Japan.
"Playing the best teams in the world is not all that easy but we have learned a lot," said their coach Bruce Mwape.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)