Leigh Halfpenny looks set to miss the start of Wales' Six Nations campaign.
The Scarlets fullback has not played since suffering concussion during Wales’ victory over Australia on November 10th.
Halfpenny has seen a specialist, and Scarlets head coach Wayne Pivac reported on Tuesday that the player would not feature for "three to five weeks".
Wales’ opening Six Nations game is against France in Paris on February 1st, followed by an appointment with Italy in Rome eight days later.
Halfpenny, 30, went off late in the Australia match after being on the receiving end of a late challenge from Wallabies centre Samu Kerevi, who avoided any punishment.
He was selected to play for the Scarlets against Cardiff Blues 10 days ago, but was a late withdrawal after suffering headaches.
And Pivac has now revealed the outcome of 80-times-capped Halfpenny’s further medical assessment.
“Leigh has seen the specialist and won’t be used for the next three to five weeks,” Pivac said. “He will continue training and doing what he’s been doing, and then he will be reassessed.
“It will be somewhere between three to five weeks, but these things take time. That’s the time-frame we’re looking at. Leigh won’t play before that time, that will be the earliest. We will pass on the medical information to the Welsh Rugby Union.
"That will then be [Wales head coach] Warren's [Gatland] call as to what he does, because the tournament runs for longer than that.
“He’s running, he’s training, and from time to time I think he’s been having bouts of [headaches]. He’s as frustrated as anybody is, but his health and well-being comes first.
"Lots of players have come back from it [concussion] before. Justin Tipuric and Aaron Shingler have had spells out, and both those players have returned to the top of their game at some point. There's no reason why that won't happen with Leigh."
