Wales star Leigh Halfpenny will see a concussion specialist in a bid to return from the injury that has sidelined him for almost two months.
Halfpenny has not played since Wales' clash against Australia in Cardiff on November 10.
The Scarlets full-back went off after a late challenge from Wallabies centre Samu Kerevi.
He was selected for the Scarlets against Cardiff Blues last weekend, but was a late withdrawal after suffering headaches.
Now Scarlets head coach Wayne Pivac has revealed Halfpenny, capped 80 times by Wales, will now receive further medical assessment.
"He is seeing a specialist, and that will hopefully give us an accurate time-frame for him in terms of coming back to play," Pivac said.
"We will know more next week, hopefully.
"It has been about eight weeks now, so we want to get some reassurance that we are doing the right things and make sure we stay on track.
"Leigh is very frustrated. You can see a leg injury, these things are easy to deal with, you can see a finish line. Muscles take this amount of time to heal, broken bones take that amount of time.
"But you don't know as much about the head injuries that occur. It is frustrating for all concerned, more so for Leigh."
Asked if Halfpenny could be stood down from playing for an extended period, Pivac added: "That is for the specialist and our medical team to make that call.
"From our point of view, we just won't risk putting him out there until he is 100 per cent."