Williams makes case for the defence

Defences will decide Australia's Women's World Cup quarter-final against Japan, according to Matildas goalkeeper Lydia Williams.

Alen Stajcic's team meet the reigning world champions on Sunday morning (AEST) in a repeat of last year's Asian Cup final.

Japan, who like to get numbers behind the ball, have conceded just two goals in four games at the tournament so far.

The Matildas, meanwhile, have only allowed one goal in three games since their 3-1 loss to United States to open the World Cup.

And Williams said defences would prove decisive in Edmonton.

"I think both teams … we're quite strong in transition, we're playing possession-based football as well as they are," she said.

"So I think defensively it's going to be whoever has the best defence and saves will definitely win the game."

Williams said she expected a somewhat familiar outing to the round of 16, when the Matildas overcame Brazil 1-0.

The 27-year-old shot-stopper had to make multiple saves, particularly from range.

"They [Japan] are an excellent footballing country," she said.

"Obviously they have some quality strikers with their shots so that [long-range shooting] is obviously something that we have to look out for.

"Same with Brazil, they're going to shoot, they're going to play intricate passes around the box.

"I think the defence is going to have a really important role this game."

While Japan have mostly cruised into the last eight, the Matildas were tested in the group of death before the win over Brazil.

And those challenging encounters have only made Australia better, according to Williams.

"I think it makes us stronger," she said.

"As Australians in general, I think the number of big guns that you knock off throughout a tournament or a sporting event I think you grow as a nation and you grow in the Aussie spirit and especially having all the support from home I think is really beneficial for us."