The explosive winger will miss about half of next NRL season after dislocating his shoulder while playing for New Zealand against England last week.

The Raiders say he will be out of action for at least six months and have pencilled in a return between rounds 11 and 14.

Back up halfback Ata Hingano is already in the rehabilitation group after suffering a similar injury in Tonga's historic Test against Australia last month.

But it is understood Rapana's injury is significantly worse than Hingano's.

Canberra were without star hooker Josh Hodgson for more than half of their 2018 campaign after he ruptured his ACL representing England at last year's World Cup.

It left the Raiders short on the field, but also financially as they had to include him in their salary cap.

The club applied to the NRL for salary cap dispensation to sign another player, but the request was knocked back.

Being one of the Raiders' highest-paid players, Hodgson's situation forced the NRL into action and changed the rules to allow clubs to apply for salary cap relief for players injured on international duty.

Canberra were almost out of finals contention when Hodgson returned in round 15.

Raiders chief executive Don Furner said the club would consider applying for compensation to help with the loss of Rapana.

That could pave the way to sign a halfback to cover Hingano, with Aidan Sezer and Sam Williams starting the season as the Raiders' only recognised halves.

Hingano is expected to be back in action between rounds six and eight.

"Our plan would be, if it's going to be six-seven-eight months, then we'll definitely look at it," Furner told reporters on Monday.

"But it's a long process before we put any applications in to them (the NRL)."

Furner was speaking at an announcement of the club's new training and administration base in Canberra's CBD.

The Raiders are hoping to shift their headquarters from Bruce, 15 minutes outside of the city, to Braddon by November next year.

Australian Associated Press