Triple Crown hero Williams aims to make the most of starting spot against Australia.
Triple Crown hero Scott Williams is determined to grab his chance at centre stage on Saturday. (KO 11am UK time)
The Scarlets midfield ace had to contend with a place on the bench during the Six Nations, with Jamie Roberts and Jonathan Davies established as the central axis.
But Williams played a super-sub role and scored the famous match-winning try at Twickenham as Wales clinched the Triple Crown.
Now, with Roberts ruled out with a knee injury, Williams hopes to replicate his Triple Crown form from the outset against Australia.
"I'm just really happy to have the opportunity to start a game," said the 21-year-old. "I've played a lot coming off the bench, with Jamie being in great form.
"This is my opportunity now and I will do my best to try and take it. It's my big chance on the weekend."
Williams, who will win his 13th cap in Brisbane, was selected ahead of James Hook and Ashley Beck. He will form an all-Scarlets midfield with Rhys Priestland at fly-half and Jon Davies at outside centre.
He reckons the familiarity will be a major advantage but insists Wales face a daunting challenge against a wounded
"I think it's an advantage because we've trained and played a lot together," added Williams. "We are used to each other.
"We know we are going to have our work cut out. Australia are not going to be a pushover. They had a really scrappy game against Scotland and were unlucky there.
"But we are just concentrating on what we are taking into the game now. We have got a massive opportunity to put a stamp on a southern hemisphere side."
With Liam Williams forced out of the World Cup through injury, lock Luke Charteris and Skills Coach Neil Jenkins say they have to put yesterday's defeat behind them as Wales now look ahead to another physical encounter against South Africa in the quarter-finals of the Rugby World Cup.
WRU Consultant Head of Physical Performance Paul Stridgeon praises the Physical Performance department for their work and dedication as he addresses the media ahead of Wales' Pool A clash against Australia
Twelve young people have been selected to follow a one year WRU Coach Core apprenticeship programme. Coach Core was set up by the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry as part of the Olympics legacy in 2012 and the Duke of Cambridge was on hand to meet the apprentices on their first day in the job. The programme has been funded by the Hunter Foundation.
The WRU has launched a campaign to create a long term legacy for Welsh club rugby by highlighting the advantages of volunteering. Rhian Edwards, a volunteer at Seven Sisters, has enjoyed many benefits of her volunteering at a grassroots rugby club including being part of the Rugby World Cup volunteer workforce after being nominated by the WRU - and the WRU is asking for more people to develop their 'Welsh rugby roots'.