The Australians were confident heading into the tournament, but were stunned 2-0 by the Canadians in their first game of the campaign on Thursday morning.

An early blunder in defence and a counter attack late in the second half were the sources of the downfall.

Canadian defender Shelina Zadorsky was sent off after 18 minutes and Matildas coach Alen Stajcic expressed his disappointment about the second half performance and believed it was deplorable considering the numerical advantage they had.

“I can’t remember one chance in the second half to be honest,” Stajcic said.

“I thought we rebounded really well in the first half, we were the better team when it was 11 V 11.

"We created a number of chances during that period and we were dangerous on a lot of occasions.

“It was the second half that was extremely disappointing, we had an extra player for the second full 45 minutes and we just lacked the decision, creativity, awareness and quality you need in the front third to unravel a hard working defence.

“Credit to the way Canada worked in that half, tirelessly preventing us.”

The Matildas now have to forget about the loss and turn their focus on Germany who are ranked second in the world and comprehensively defeated Zimbabwe 6-1 this morning.

Stajcic conceded the circumstances had now changed and labelled the game against the Germans as a must win if they are any chance to progress.

The Matildas boss also promised a stronger performance on Sunday.

“We’ll be full strength, and this is a big game for us now, hoping to get to the finals where it’s life and death,” he said.

“But now this game is life and death for us and Germany is going to see the full power of the Australian side in its full attacking force rather than what we saw today.

“You have to pick yourself up, you can’t sulk for too long. The challenge ahead is too big, we haven’t come this far spending time in Brazil to have a sulk.

“We’re mentally tough, we’ll have a look at what we did well and what we didn’t and we have to refocus quickly.”