Hayley Raso scored twice for Australia in a statement 4-0 win over Canada as the fired-up co-hosts booked their place in the last 16 of the Women's World Cup on Monday at the expense of the Olympic champions.

Tony Gustavsson's team came into the clash with their backs to the wall, needing victory to ensure they made the knockout round after a stunning 3-2 defeat at the hands of Nigeria left them on a knife-edge.

In front of a heaving Melbourne Rectangular Stadium, they thrived on the pressure to the delight of the raucous 27,706 fans, consigning Canada to an early flight home.

Real Madrid's Raso put them ahead in the ninth minute, firing low into the corner after captain Steph Catley fed a teasing low cross.

They had a goal controversially disallowed 10 minutes before the break, but the rampaging Matildas put it behind them and Raso made sure on their very next attack with a close-range tap-in.

A shellshocked Canada made four changes at half-time, but the comeback never materialised and Mary Fowler bagged Australia's third from a counter-attack before Catley sealed victory with an injury-time penalty.

The win left them top of Group B ahead of Nigeria, who drew 0-0 with Ireland in Brisbane, and set them up for a clash against the second-placed team in Group D – likely Denmark or China – in the next round.

But it was the end of the road for Canada, who would have been through with a draw.

All the chat ahead of the game was whether Australia's Sam Kerr would play after missing their opening two games with a calf injury. The Chelsea star was on the bench, but wasn't risked with her team in complete charge.

They home side was boosted by the return of Manchester City's Fowler – who replaced Kerr in their 1-0 win against Ireland but missed the Nigeria game with concussion – but it was livewire Raso who gave them a dream start.

After a cagey opening, Catley was set free down the left and her curling ball found Raso who took two touches before smashing it into the corner.

It was called offside, but VAR awarded the goal and the stadium erupted.

Canada grew into the contest, but their chances were few and far between.

Australia thought they had their second when Fowler rifled home from close range, but after a long delay, VAR found that Ellie Carpenter was fractionally offside and it was disallowed to the disgust of fans.

Unperturbed, they launched straight into another attack and this time the goal counted, with Raso making no mistake from two yards out after the ball pinged off a Canadian defender from a corner.

Canada made wholesale changes at the break in a bid to revive their fortunes, but Australia resumed where they left off.

Raso and Kyra Cooney-Cross both went close before Fowler bagged the third in the 58th minute after Caitlin Foord beat the offside trap and cut the ball back.

Catley then stroked in a penalty at the death to wrap up the win after a Jessie Fleming foul was punished on review. (AFP)