Wallabies looking to take on the Springboks up front in Perth

The Bok bruisers sent many an All Black backwards during the recent Rugby's Greatest Rivalry Tour. Williams knows that the battle for the match will likely be won or lost up front. And if they gain some parity with the forwards, it may free up the likes of Harry Potter Joseph-Aukuso Suaalii out wide.

"You're fully aware that it's going to be a physical game, and it's going to be won up front," Williams told AAP.

"We've been training for that this week. We know what's coming. We've got to go out there and make sure we nail our processes. Be physical and lead it on that front. And then let guys like 'Potts' and 'Sua' do the magic.

"I know that we're backing ourselves in the training that we're doing this week, and we know that if we go out there and set the tone physicality-wise, we'll be a good shot."

But Williams is under no illusions as to the challenge that awaits. While Bok boss Rassie Erasmus has made 13 changes to the settled side that dominated the All Blacks in Baltimore two weeks ago, there is still ample experience on the park. 

The highest-capped Bok of all time, Eben Etzebeth, starts in the engine room alongside warrior Franco Mostert, while more experience is on the bench with Malcolm Marx and Lood de Jager.

As such, Williams gave credit where it's due.

"They've won World Cups, and they obviously had a successful tour with New Zealand," he continued.

"They've obviously named quite an experienced team. In the locks, they've got (230) caps between them. They've got quite a lot of experience out in the park.

"We're really pumped to get out there and put in a good performance."