Melbourne Storm head coach Craig Bellamy has revealed the club are hopeful Cameron Munster's groin injury isn't as bad as first thought.

Munster was taken from the field just before halftime during Sunday afternoon's game against the Parramatta Eels in agony after appearing to suffer a groin injury.

The five-eighth has been struggling with the injury throughout the season, and missed the opening weeks of the campaign with the struggle.

While the new blow throws his State of Origin participation into doubt, Bellamy said the on-field assessment was different to the one provided post-game as medical staff at the club continued to assess the injury.

"He was [pretty devastated]," Bellamy said during his post-match press conference.

"It's obviously pretty early and I didn't get a real report straight away, but I think when it first happened, the medical staff thought it was fairly serious or not good at all.

"I don't think they think it's quite that bad now, but what that means, like, I don't know. I don't think we will know till he cools down and has scans and see how it feels.

"Like I say, he has been carrying it for a bit. It's not good for us, but hopefully the diagnosis after the game is the one and not the one during the game."

The coach said Munster would take the injury hard, but said the club would support him over the coming weeks as he begins his recovery.

"There isn't much you can say really. You just have to wait for the scans and put a plan in place after that. That's all you can do. He is a passionate bugger, and he loves playing Origin. He knows he is one of our leaders now, and we rely a lot on him. He will be upset over that," Bellamy added.

"He is a great team guy, he has genuine care for the team, it's going to be hard for him but we will support him and get right behind him."

It has been suggested Munster will need surgery at some point to fix the issue, but it's understood if he needs it now, he will miss the remainder of the season.

"I think if he has it [surgery] now - and I'm not 100 per cent on this - but if he has the operation now he probably won't play again the rest of the year if it's the operation they think he needs," Bellamy said.

Queensland pick their State of Origin side for Game 1 after Round 12, while Melbourne will be left scrambling with back-up half Jonah Pezet sidelined for the remainder of the year after injuring his ACL in a QLD Cup game a handful of weeks ago.