LIAM Williams has been backed to provide Wales with a cutting edge against Australia on Saturday – but has been warned to keep his emotions in check.

The in-form Scarlets speedster is selected on the left wing for the Millennium Stadium clash with the Wallabies following George North's move to midfield.

It will be the sixth Test in a row that Warren Gatland has selected the 23-year-old but Williams has been told by the Wales management that at times he needs to curb his enthusiasm.

His illegal tackle on Cornal Hendricks in the closing stages of June's 31-30 loss to South Africa in Nelspruit led to a penalty try, meaning the Springboks took the lead with a simple conversion rather than having to try and add the extras from the right touchline.

Williams' scant regard for his own safety can be a strength, but also a weakness.

"He will bring creativity with his lines of attack; he's quick and has the ability to beat the first player. He also has the heart of a lion," said assistant coach Rob Howley.

"His ability sometimes to go outside that little box and his emotional control and intelligence will be important over the weekend.

"International rugby is about discipline, international rugby is not having a yellow card or a red card. It's about having 15 men on the park. That will be key for both sides on the weekend.

"That's the bottom line in terms of your starting point in the international game: discipline is huge.

"It's an area where we had a hot debrief and Liam was part of that, going back to the last game and the first Test against South Africa when he could possibly have had a yellow card.

"So it's always a work-on for players and it's a work-on for Liam, but I have no doubt in attack he has the creativity and the speed to create something out of nothing."

Howley is confident that North will thrive in midfield and will be aided by the reassuring presence of Jamie Roberts, who will guide the Northampton winger through in defence.

"George has gone there before, having been selected against France last season and gone there against Australia (switching during the game last autumn," said Howley.

"He is going to be stressed defensively in terms of his decision-making, but we are more than comfortable with George playing in the centre, and having another Lion in Jamie alongside him will give him confidence."