Luke Keary is set to miss the opening game in this year's State of Origin series after suffering a second concussion in five weeks.
The half-back received a heavy knock to the head during Sydney Roosters' 38-12 loss to Newcastle Knights on Friday, meaning he will require clearance from an independent neurologist before being allowed to play again.
Keary, who previously underwent a concussion assessment during his side's victory over Melbourne Storm on April 19, was seen as a potential starter for New South Wales.
However, Blues coach Brad Fittler is set to be without the 27-year-old for the series opener against Queensland at Suncorp Stadium in Brisbane on June 5.
"Luke's been in great form, he was part of the squad last year and Luke was looking like he was going to break into the team," Blues advisor Greg Alexander told ABC Grandstand on Saturday.
"But I don't think Luke will take part, he won't be fit for game one."
Fittler is due to name his Blues team on Sunday, after the conclusion of round 11 in the NRL season.
Meanwhile, Keary's Sydney team-mate Jared Waerea-Hargreaves has been cited by the match review committee after an incident in the defeat to Newcastle.
The prop received a Grade 1 charge for making dangerous contact with the head or neck area following a tackle on Kalyn Ponga in the second half.
The Roosters have the option of entering an early guilty plea, though such a course of action would mean the player receiving a two-game ban.