Eddie Jones and Michael Cheika say Australia and Argentina are works in progress, but with the clock ticking to the Rugby World Cup, both coaches desperately need a win when the teams meet on Saturday.

Jones's Wallabies and Cheika's Pumas suffered heavy defeats, to South Africa and New Zealand respectively, to kick off the Rugby Championship last weekend.

It makes their clash at Sydney's Parramatta Stadium a must-win to boost confidence and get their preparations for the World Cup in France in September-October on track.

"They're just in construction like where we're starting our season too," said Cheika, a former club mate of Jones who is keen to get one over his fellow Australian.

"He's a high-quality coach and you always want to go up against high-quality coaches just to test yourself.

"The biggest thing with Eddie is he's a competitor and he wants to win, and I'm pretty much the same."

After crashing 41-12 to the All Blacks in Mendoza, where they conceded three tries in the opening 12 minutes, Cheika has swung the axe with four changes to his starting Argentina team.

It sees wing Rodrigo Isgro, part of the Sevens side that won bronze at the Olympics in Tokyo, handed a debut.

Prop Francisco Gomez Kodela and flanker Santiago Grondona also come in to shore up the scrum, while Jeronimo de la Fuente will play at centre.

The Pumas head into the match looking to win back-to-back games against Australia for the first time ever after a 48-17 thrashing -- their biggest margin against the Wallabies -- last year.

But that was on home soil. Their away record is poor, winning three of their last 16 against all opponents.

"I'm telling the lads just prepare day by day, be your best day by day and good things will happen for us," said Cheika, who coached the Wallabies until 2019.

- Rough plan -

Jones has also made changes, two enforced by injury, following their humbling 43-12 loss to a second-string South Africa at Pretoria in his first game in charge. 

Co-captain Michael Hooper is sidelined with a minor calf strain, opening the door for Fraser McReight at openside flanker.

Jed Holloway will line up alongside him in place of the injured Tom Hooper at blindside.

Mark Nawaqanitawase is preferred to Suliasi Vunivalu on the wing, Samu Kerevi takes over from Reece Hodge at inside centre and lock Richie Arnold got the nod instead of Nick Frost.

Jones said he always intended to make changes for the second Test of his reign as he works to nail down the best XV for the World Cup.

"We have a rough plan of what we want to do. Our aim is to get to the World Cup in the best position and we have five games to do it," said the coach, who inherited from the sacked Dave Rennie a team that lost nine of 13 internationals last season.

"We are obviously a new team and a new coaching staff so we are finding out where we are at. We didn't have a number in place but we were always going to make some changes.

"It is not about guys solidifying positions, it's about building depth so we can take a team to the World Cup and in every position we have three players with the quality we need to have," he added.

Of those five matches, two will be against the All Blacks before they head to Europe for a clash with France in their final game before the World Cup.

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