Penrith and NSW rocked by devastating Nathan Cleary news

The Penrith Panthers have copped a devastating blow with Nathan Cleary potentially ruled out for the rest of the season after suffering a shoulder injury in State of Origin II.

Cleary played through the injury on Sunday night, but went for scans on Tuesday to understand the extent of any damage, however NSW Blues coach Brad Fittler all but ruled him out for the third Origin clash.

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The Blues will be hoping to complete a clean sweep of Queensland when the series swings back to NSW, following their 26-0 victory on Brisbane last Sunday.

Cleary skipped the post-game celebrations to immediately begin icing his shoulder, despite vowing he wouldn't miss the final Origin match.

However in a radio appearance on Tuesday morning, Fittler suggested the injury could be more serious than initially thought.

"We'll get his results today, but it's looking pretty unlikely that he'll play. He went down pretty hard on his shoulder," Fittler told SEN Radio.

"We're just sort of hoping that everything will be good enough that he'll be back fighting for the Panthers soon enough.

"He's had a great start to the season, and he's under a lot of pressure, but he more than stood up on the big stage."

Fittler gave little indication of who the Blues would look to call up to replace the 23-year-old.

NSW and Penrith head of performance Hayden Knowles said the silver lining for the Panthers was that Cleary had been able to initially play through the injury.

“The one positive is he finished the game, and if you have to bring them from the field, that’s when it’s a real worry,” he said.

“He played for the majority of the game with it. He had it looked at at halftime and got it strapped. Even in the middle of the second half we asked him if he wanted to come off and he said, ‘No’.

“An hour after the game I asked him about game three and he said, ‘There’s no way I’m missing it’.

“But the type of pain he was in, the physios suggested he could be looking at anywhere between one and four weeks, which is a big range.”

Penrith Panthers sweating on Nathan Cleary shoulder scans

Penrith will be hopeful to see Cleary back on the field sooner rather than later, with the 13-2 Panthers struggling somewhat during Cleary's Origin absence.

Any injury would represent a significant blow to the Panthers given Cleary's record alongside Jarome Luai, although they do have Matt Burton to fill in at halfback.

Fittler would not enter into speculation on Cleary's Blues replacement if the 23-year-old is ruled.

Adam Reynolds and Mitch Moses loom as the most likely options, while a Mitchell Pearce return is not out of the question.

Fittler could elect to call bench utility Jack Wighton into the starting side at five-eighth and move Jarome Luai to halfback.

Alternatively, Cody Walker would be another option at No.6 if Fittler wanted to move Luai into the No.7 role.

Penrith are not able to assess their star playmaker's injury until Wednesday, with the entire Blues squad still in isolation after returning from Queensland.

Early scans have not come back good for the 23-year-old, who awoke in serious pain on Monday morning leaving Panthers officials with real concerns.

It's believed the Panthers could push back any surgery until the end of the season, believing the Dally M leader can play through the pain.

With AAP

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