Originally overlooked despite a stellar season with Canberra, Croker was called into the PM's XIII squad on Wednesday in place of Raiders teammate Jack Wighton, who has a minor knee strain. Wighton is expected to be fit for the start of Canberra's pre-season, beginning in late-October.

Croker's 202 points this season was third in the NRL, behind Dally M medallist Johnathan Thurston, but the 24-year-old now wants to prove a point to representative selectors.

Knocking on the door on Country Origin selection the past two years and called in to train with the NSW Blues this season, Croker said he's determined to make the most of his representative breakthrough.

"It's a good opportunity for players to put their case forward for Four Nations but also just for future representative games," Croker said. "The window's not shut for anyone for the Four Nations."

"Everyone's goal in footy is to play rep games and win grand finals. Like [Raiders coach Ricky Stuart] said a while back, the more rep players we have in the team, the better the team you have. Obviously I've got future aspirations, it's good to get a start."

Australian coach Tim Sheens said the Prime Minister's XIII match against Papua New Guinea would influence selection for the Kangaroos, issuing a challenge to Raiders forward Josh Papalii to prove himself at prop and cement a position in the Four Nations opener against New Zealand in Brisbane on October 25.

"Canberra probably need him more on the edge, but his representative career may lend him to play prop as well. We've got a problem there, particularly for this Four Nations, so this gives him the chance for more game-time ... which may bring him into the first squad, the first 17 that play New Zealand in game one. It's not a promise, but it's an indicator we're looking at it."

There is potential opportunity in the backline too, with Bulldogs centre Josh Morris in doubt to play on after this weekend's grand final.

Melbourne's Will Chambers and Newcastle teenager Sione Mata'utia will start in the centres, but Sheens assured Croker would get his chance to play, given the match is unlimited interchange.

"He's certainly been a rock down there in Canberra, it'll be a good experience for him to play with new players," Sheens said.

"I'm not going to raise any false hopes but I'm going to kill them either. The Four Nations is still weeks away ... they all get a last minute opportunity to show what they've got before we sit down and finalise the Four Nations squad."