Roommate and close mate Boyd Cordner could become the unwitting beneficiary of Luke Lewis’ sickening Rugby League World Cup-ending injury.

The rising Sydney Roosters star was shattered for Lewis, who suffered a dislocated shoulder after colliding heavily with an advertising hoarding during Australia’s 34-2 win over Fiji in St Helens on Saturday night.

Scans will determine the severity of the injury but Lewis has been ruled out of the rest of the tournament.

Cordner made 21 tackles and 75 metres in a solid Test debut off the bench at Langtree Park and Lewis injury could open the door for him to play a larger-than-expected role at the tournament for the Kangaroos who next face Ireland in their final group match.

Given the circumstances it wasn’t something the 21-year-old was ready to entertain.

“I’m rooming with him (Lewis) and class him as one of my best mates,” Cordner told AAP.

“To see him go down like that and the way it happened, it’s shocking.

“I’m a bit angry actually to see a mate go down like that.

“He’s such a good bloke and he doesn’t deserve it to happen to him but he’ll be right.”

Cordner and the likes of Raiders hardman Josh Papalii will certainly figure in Tim Sheens’ selection plans to replace Lewis in the bigger games ahead though the coach was also keen to draft a replacement from Australia – assuming tournament rules allow him to.

“That’s being looked at but I’m uncertain of the rules there,” Sheens admitted.

“I think for a serious injury like that, I’m hoping we will (get a replacement).”

A philosophical Lewis said he hoped to stay on in the UK for the rest of the tournament.

The 30-year-old’s injury was so painful he was in a state of minor shock.

After being helped off the ground it took around 15 minutes for medical staff to get his shoulder back into place.

Lewis had been one of Australia best players and scored a try moments before the incident occurred.

Chasing through a kick with ten minutes to go, he collided with Michael Jennings and slid at speed on wet ground into the World Cup sign, set at the end of the short Langtree Park in-goal area.

Lewis said he could remember little about the incident but praised his teammates for helping him get through the excruciating pain in the dressing rooms.

“It was pretty bad,” Lewis said.

“We couldn’t get it back in, the pain was pretty horrible.”

Lewis was confident he would be fit to start next year’s NRL season with the Sharks.

Sheens said Lewis’ injury marred an otherwise positive night for his side.

The Kangaroos overcame atrocious conditions in the six-tries-to-none win, which puts them top of Group A.

Papalii grabbed a try on debut while Darius Boyd, Michael Jennings, Daly Cherry-Evans and Josh Morris also had four-pointers.

Cherry-Evans impressed in place of the rested Cooper Cronk while man-of-the-match Thurston slotted several remarkable sideline conversions in strong winds and heavy rain.

Sheens said Australia still had plenty of area for improvement.

“I think we were rusty and we did some silly things but defensively we were very good,” Sheens said.

The Kangaroos play Ireland, which lost 42-0 to England, in Limerick on Saturday.