North Queensland have been forced to rest Michael Morgan for Saturday's NRL clash with Newcastle after the playmaker's State of Origin head knock.
Morgan was left groggy after a heavy clash with NSW forward David Klemmer in the second half of Queensland's Origin I victory on Wednesday night.
Despite not returning for the remainder of the match, Morgan passed cognitive tests and was hoping to take on the Knights in Townsville.
But coach Paul Green says the NRL's concussion protocol and the short turnaround between fixtures make it impossible for Morgan to be considered.
"He passed that part of it but it's a five-day protocol and we play in three days," Green said.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
"He's pretty keen to play. He feels good and he pulled up good but unfortunately that's what the rules are, so he won't play."
Morgan will be replaced in the line-up by Ray Thompson, who'll make his 100th NRL appearance in the fixture.
The remainder of the Cowboys' Origin stars - Johnathan Thurston, Matt Scott, James Tamou and Justin O'Neill - have been cleared to play.
The bottom-of-the-ladder Knights head north without former NSW winger Akuila Uate.
The Fijian flyer has been dumped to reserve grade in place of Jake Mano.
Green says that selection shows Knights coach Nathan Brown is serious about turning around the club's fortunes.
"For him to be dropped from the team, it does make a statement," Green said.
"Brownie's obviously drawn a line in the sand. They have their standards."
Korbin Sims is suspended for the visitors, with veteran Jeremy Smith to return from a bicep injury in his place.
Queensland winger Dane Gagai is also expected to line up for the Knights despite his Origin exertions.
NORTH QUEENSLAND v NEWCASTLE - Key match stats
* North Queensland's record at home since 2014 is the best in the competition with 27 wins from 32 starts.
* Newcastle have scored over 12 points in just five of their 12 matches and have been scoreless in three of their past six games.
* The Cowboys average just under 26 points per game this year, the third best tally in the league.
