Davies-Uniacke, Hartung in Roos' opener

But coach Brad Scott has stopped short of confirming veteran ruckman Todd Goldstein's place in the Kangaroos' 22, with fellow big man Braydon Preuss also in the mix.

Goldstein's strong pre-season form has raised hopes the 29-year-old can return to his best after a lacklustre 2017.

While Goldstein is the frontrunner to line up against the Suns on Saturday night in Cairns, the 206cm and 109kg Preuss has also impressed Scott with his physicality.

The pair played one half each during the Roos' final trial match against Richmond.

"We'll announce that tomorrow," Scott said on Wednesday when asked which of the pair had been picked.

"The way AFL footy is right at the moment, it makes it incredibly difficult to play two genuine ruckmen. I don't think there's anyone else in the competition who's doing that at the moment.

"When you add in the fact that we've got a 200cm key forward in Ben Brown, it makes it even harder.

"We've got that ruck support that Browny can give us so it's more than likely we'll go with one ruck and we'll continue that conversation throughout the year."

Scott confirmed that important defender Robbie Tarrant has been selected despite being hospitalised after copping a knock to the kidney during the loss to Richmond.

Davies-Uniacke will slot into the senior side immediately after being taken with pick No.4 in last year's national draft.

The Roos also hope to get the best out of endurance king Hartung following his delisting by the Hawks.

"He's picked himself," Scott said of Davies-Uniacke.

"He's an exciting young player for us, there's no doubt about that.

"He can play as a permanent forward, he can play inside or outside midfield roles, and because he's such a good decision-maker and good kick, he could probably play off half-back if we wanted him to."

Australian Associated Press