The Matildas have been taught a “lesson” by Japan a year out from a potential Asian Cup meeting with the women’s football powerhouse.

The Aussies were thumped 4-0 in what was their worst ever defeat to Japan and a disastrous debut at the SheBelieves Cup on Friday morning.

Japan had 18 shots at goal to Australia’s one – the Matildas’ lone strike came late in the piece when Charlotte Grant hit the woodwork.

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Australia struggled with the ball and without it, leaking some goals which should ordinarily be stopped.

What made the performance more concerning was the fact Australia trotted out its strongest possible line-up, and still looked nowhere near the quality of Japan.

“Disappointing doesn’t really come close to covering it,” former Socceroos player Andy Harper said on Paramount.

“It’s a morning which did not work. The plan was to pick the most stable, the strongest, most experienced combination (of players)… that’s my interpretation.

“By picking that team what you’ve not done is invest in some other alternative combinations, individuals. And that’s fine, you make that decision, you run with it.

“The decision they went with has just not worked today. Very, very poor.

“We actually didn’t look like we knew how we were going to beat Japan. There was no discernible plan.”

When the team was down 2-0 at half time Harper called it “beyond less than acceptable”.

“For a team that’s aspiring to become Asian champions on home soil, on the back of all the euphoria this team has justifiably created, they are so far off that standard at the moment,” he said.

And interim Matildas coach Tom Sermanni agreed.

He says the shocking loss should teach the team some valuable “lessons” to hopefully avoid a similar result when Australia hosts the Asian Cup next year.

“Firstly, Japan were very good. It was a bit of a football lesson today, if I’m being honest,” Sermanni said.

“We were poor in a lot of areas. Things just didn’t work out for us.

“The positive of this is it gives us a lesson for how you play Japan, and how we go about playing against them.

“We haven’t had a lot of preparation heading into this camp so when things start to go wrong, it’s a bit harder to fix it.

“Japan were exceptional, and we didn’t really get close to them. It’s a great lesson heading to the Asian Cup next year because it gives us an idea of what we need to do to win that tournament.”

Concerning images were published post-game of star players Hayley Raso and Kyra Cooney-Cross appearing to bicker following a Japan goal.

One-time Matildas player Grace Gill was stunned at how far off the pace the Aussies looked in Houston.

“We just saw a chasm between the two teams,” she said.

“We saw a classy Japan – they were organised, they were disciplined, they knew their roles both in attack and in defence.

“We saw a really poor performance for the Matildas. Those two two things came together in a perfect storm.”

Australia is contesting the invitational SheBelieves Cup for the first time.

The Matildas next take on the powerful USA on Monday morning (AEDT).

“It was a bad performance from us and we need to regroup, refocus,” team veteran Ellie Carpenter said.