Switzerland kept a clean sheet through the group stage of the Women's World Cup but only scored two goals through three games, and so coach Inka Grings said La Nati have worked intensively this week on the offensive part of their game.

"This was definitely one of our focus points this week . . . it was something that we analysed intensively, we talked through with the team and also take the offensive players, assertive players, bring them more into the team," Grings told a press conference on the eve of Switzerland's final 16 game against Spain at Auckland's Eden Park.

Grings' 20th-ranked squad topped Group A in their second World Cup appearance, with a 2-0 win over the Philippines and scoreless draws with Norway and New Zealand.

"Of course we have to be more assertive in that run towards the goal," Grings said. "We have really understood that message and we have helped to convey that with videos. I can also read from the body language from the players that it's been quite an intensive week."

Sixth-ranked Spain, considered the favourites on Saturday, albeit in a tournament of numerous upsets so far, kicked off their campaign by beating Zambia and Costa Rica by a combined score of 8-0. But Japan ran roughshod over La Roja in a 4-0 victory to cap the group stage.

"(Spain) have shown us weaknesses that we have analysed intensively with our team, however (Saturday) of course is a different match," Grings said.

"Spain has very strong players. We don't want to focus and shouldn't focus on just one player. We look at them as a compact and strong team."

The Swiss were ousted in the round of 16 in their only other World Cup appearance in 2015.

The winner of Saturday's match will play the winner of the Netherlands and South Africa next Thursday.