'Never compromise': NRL launch investigation into Boyd Cordner head knock

The NRL is set to launch an investigation into how NSW Blues captain Boyd Cordner was allowed back onto the field during the first game of the State of Origin series, despite suffering a head knock in the first half.

Cordner was brought from the field after copping an accidental hit to the head while tackling Queensland opponent Felise Kaufusi.

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The 28-year-old passed a mandatory HIA (Head Injury Assessment) after sitting out for the compulsory 15 minutes under the NRL’s concussion protocols, with Blues doctor Nathan Gibbs reportedly standing by the decision to let Cordner play on.

On Thursday evening the Sydney Morning Herald reported the Blues had been issued a ‘please explain’ after the NRL’s chief health officer Paul Bloomfield reviewed footage of the match.

ARLC chairman Peter V’Landys backed the investigation, saying the safety of players was their primary concern.

“We will investigate it because we will never compromise on player welfare, it is paramount,” he said.

“There is nothing that competes with it.”

Cordner played out the rest of the Blues’ shock loss to Queensland, with the Maroons erasing a 10-0 deficit at half time to win 18-14.

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Cordner's concerning history with concussion is growing, but NRL teammate Luke Keary insists players have to trust they're not being put at risk by head injury experts.

The NSW and Sydney Roosters stars have battled concussion complications over the past two years, both spending time out of the game on club orders.

The protocols that allowed Cordner to play on have now come under fire from a leading clinician in concussion and dementia services at Macquarie University, Dr Rowena Mobbs, who has called for a review into the HIA process.

Clinical co-director of the Australian Sports Brain Bank, Mobbs assesses high-profile Australian sports people who have suffered years of head knocks and has authored a study on chronic traumatic encephalopathy (CTE).

"Players are clearly concussed at the time of impact on the field," Dr Mobbs said.

"The crowd and commentators can see that this is a brain injury.

"There is video evidence of brain injury, and they should be off for the game, and the next, with all caution taken.

"How many sub-concussion knocks as well as concussion knocks are players sustaining?

"Australia has a long way to go in this field of research to understand the risk of CTE.

"We are calling for a national repetitive head trauma initiative that will involve neurologists providing a proper assessment of this long-term risk."

Concern for Cordner has grown in recent months after he admitted to suffering ongoing concussion symptoms, with some calling for the inspirational forward to retire.

With AAP

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