Michael Cheika's schoolboy World Cup trial run

Wallabies coach Michael Cheika is using schoolboy rugby talents as guinea pigs to refine his re-jigged World Cup blueprint.

Speaking publicly for the first time since the appointment of Scott Johnson to the newly-created position of director of rugby in December, Cheika told the Green and Gold Rugby podcast to expect some changes in Japan later this year.

Rugby Australia are yet to find a replacement for axed attack coach Stephen Larkham but it hasn't stopped Cheika using schoolboy and colts sides to toy with new systems.

"There’s some things that we’ll look at in our game this year that will be a bit different," Cheika said.

"We’ve run that through some different groups of people just to get opinions and we’ve come up with what I think is some really good evolutions or changes in the game.

"We’ve tried those out, got a couple of school, colts teams, had a few training sessions with them just to see what works, what doesn’t.

"(We have been testing) the things we've prepared to change in our attack against the things we've prepared to change in defence ... just to have a look at what it's like to coach it."

Finalists at the 2015 World Cup, Australia slipped to sixth in the world rankings after a frustrating 2018 season that led to Johnson's appointment.

The form of the country's four Super Rugby franchises has buoyed Cheika though, who says he's noticed competitiveness across the board when playing their South African and New Zealand opponents this season.

"There's a lot to build on but some really positive signs and it should give players good belief," he said.

Cheika, who was flying out to meet with European-based Wallabies, also name-dropped Queensland lock Harry Hockings, Rebels No.8 Isi Naisarani and Melbourne flanker Brad Wilkin as unheralded prospects who have impressed him this year.

The Wallabies will play five tests before their World Cup opener against Fiji in September.

AAP

Watch - Raelene Castle on Sunwolves axing: