Knights recruit Rory Kostjasyn is set to spend the next 12 weeks on the sidelines due to a throat injury that requires surgery.

The former North Queensland Cowboys utility needs an operation after being hit in the throat with an accidental elbow at training.

Surgery has been delayed due to swelling in the throat, Newcastle physio Tony Ayoub told Knights TV.

"We're just waiting for the swelling to settle down and that's why we've kept him away," Ayoub said.

"At the moment they can't touch it simply because it's so swollen.

"If it can settle down then he can have that surgery sooner rather than later.

"At the moment it's probably looking like 12 weeks before he can play."

With the new Telstra Premiership season to begin in six weeks, a 12-week layoff would see Kostjasyn make his Knights debut in Round 7 or 8.

Read more at newcastleknights.com.au