Rapana is believed to have left Anfield with his right arm in a sling after he was injured twice in the match, the first while trying to score a try and the second attempting to save one.

Canberra players are away in a pre-season camp but on Monday afternoon were yet to hear the diagnosis, with hopes the try-scoring machine won't miss the start of the 2019 NRL season.

The Raiders have already lost play-making utility Ata Hingano for up to the opening eight rounds through shoulder surgery, and there are fears Rapana could miss just as long if he too goes under the knife.

However, the 29-year-old could be back fit for his return to pre-season training after Christmas if he does not require an operation.

Rapana's right shoulder appeared to pop back in after the first 12th-minute incident as he played on for the Kiwis, but he later succumbed when it looked to stay out when he landed on it in in the 68th minute.

The Raiders have had rotten luck when it comes to international Tests in recent years, after hooker Josh Hodgson missed most of 2018 after injuring his knee for England in last year's World Cup.

Hingano's injury also came in Tonga's Test loss to Australia last month.

Rapana has been one of the Raiders' best game breakers in recent years, scoring 54 tries in 71 games since the start of 2016.

Australian Associated Press