Michael Morgan could miss the rest of the NRL season

North Queensland’s NRL premiership hopes have suffered a hammer blow with representative stars Michael Morgan and James Tamou ruled out indefinitely.

Five-eighth Morgan has been diagnosed with a high ankle sprain while front-rower Tamou will undergo further scans on Wednesday to determine the full extent of a nerve injury in his neck.

The Cowboys are unsure when they will be fit again but the major concern is over playmaker Morgan, who may have played his last game this year.

Typically, recovery from an injury to the syndesmosis joint takes at least four weeks, meaning he has his work cut out to play any part in third-placed North Queensland’s finals campaign.

“They can take quite a while so he’ll just be monitored and we’ll go through the normal recovery protocol, and we’ll see how he goes,” Cowboys coach Paul Green said.

“It doesn’t require surgery so that’s a positive.

“He’s a key player in our team so we want him back when he’s able to be fit and ready to do that.

“How long it takes, we’re just not sure.”

Morgan’s injury is to the same ankle he had surgery on after the Origin series and Green conceded that could further complicate his rehabilitation.

Several league identities, including Peter Sterling, have already declared that the Cowboys can’t win the premiership without 23-year-old Morgan, who has enjoyed a breakout season and taken a significant load off chief playmaker Johnathan Thurston.

Test and NSW prop Tamou has been cleared of any major damage to his neck but has still been sidelined without a return date.

He battled neck issues through the pre-season and looked in strife when he was felled by New Zealand’s Simon Mannering during Saturday’s clash in Auckland.

Green said Tamou would be a “week-to-week” proposition.

“It’ll just be a matter of, similar to last year, just waiting until all the symptoms are gone and he gets full strength back in both his arms,” Green said.

“There was no further damage done so he’s pretty positive and the medical staff are pretty upbeat about it as well.”

The Cowboys travel south to face Melbourne on Saturday night, needing a win to remain in the hunt for a top-two finish on the ladder.