Newcastle are tipped to be without second rower Jack Johns for an extended period of time after the Knights forward suffered a suspected broken arm in Saturday night's loss to North Queensland.

An attempted tackle on Cowboy Murray Taulagi left Johns grimacing and immediately holding his left arm, with the 24-year-old taken to hospital for further treatment.

Johns wasn't the only casualty for Adam O'Brien's side, with Edrick Lee suffering a head knock within 15 minutes of Johns' injury, compounding the Knights' woes.

The second half setbacks placed even further strain on the Knights' evening, with Newcastle falling to North Queensland by 20 points in Townsville.

A failed concussion test will see Lee sidelined for Newcastle's upcoming clash with Canterbury in Magic Round next week.

O'Brien is continuing to search for his first win since his side's Round 2 fixture with the Wests Tigers, having now lost seven matches in a row.

Embed from Getty Images

The double injury blow followed a late omission for star forward Tyson Frizell, who was sidelined due to illness.

The New South Wales forward is anticipated to be among six players returning to the Knights' selection frame for their trip to Brisbane.

The club are awaiting further examinations on half Adam Clune's knee, while Jake Clifford could also return after stepping away from duties for personal reasons.