Jamie Roberts has admitted Wales had their backsides kicked by Australia and that Argentina are polishing their boots.

In a frank assessment of the team’s performance in their 32-8 defeat to the Wallabies on Saturday, the Wales centre confessed he and his teammates were given a good shoeing.

“It’s certainly a kick in the backside for us, and we go into training on Monday and we have to address the issues,” said Roberts.

“Rugby is about momentum, it’s about speed of ball, and we just didn’t win that battle against Australia. They played some good stuff in attack and caused us problems, along with some poor defensive reads from us.

“Argentina will pose a similar threat with a lot of pace out wide, and if we allow them momentum, speed of ball and space in the game, it will be another tough day.”

Wales have won just three of their last 12 Tests, while they remain without a victory in the opening game of an autumn campaign since they beat Romania in Wrexham 14 years ago.

Australia could, and should, have won by a greater margin, and not since New Zealand inflicted a 45-10 drubbing on them in 2006 had Wales been so horribly outclassed on home soil.

We’ve got to learn from it,” Roberts added.

“Argentina are a formidable outfit this year, and they have improved a lot the last few years. We will rock up to training on Monday and learn from our mistakes and go again.

“We’ve been there before. A lot of us have been there before. It was a bad day at the office for us, and it happens in rugby, it happens in sport.

“You would like to blame a lot of different things for a result like that, but there is no point being too complicated about it. They beat us.

“The speed of ball, and certainly with the possession in the first-half, they blew us away. You can dress it up all you want, but we lost the gain-line battle.”

Wales’ interim head coach Rob Howley looks certain to make changes for the Pumas encounter, with flanker Sam Warburton and lock Alun Wyn Jones likely to be back, and could have key backs Liam Williams and Jonathan Davies available.

But scrum-half Rhys Webb now appears a fitness doubt for the remaining three November games after suffering an ankle injury.

Howley, meanwhile, could also look at possible starting spots for fly-half Sam Davies and lock Cory Hill, two Test rookies who settled comfortably and impressively when they made second-half appearances off the bench.