Forward Richie Gray has been ruled out of Scotland's Six Nations opener with Wales on Saturday.
The 64-times capped Toulouse lock sat out last week's three-day training camp in Edinburgh with a calf injury.
Now the Scottish Rugby Union has confirmed the 28-year-old will remain in France this week for treatment with his club side's medics.
— Scottish Rugby (@Scotlandteam) January 29, 2018
But while he will miss this weekend's Cardiff clash Scots head coach Gregor Townsend hopes to have him back for the later stages of the tournament.
Assistant coach Mike Blair said: "Richie wasn't involved in the autumn or the summer tour so it's a situation we have been able to handle in the past.
"Obviously he is a quality player and a guy we're really keen to see back and how he fits in – but he also needs to get himself right. There's no point having him here if he's not 100 per cent.
"When will he be back? Sooner rather than later but we can't put an exact time on it right now."
Gray's absence means his brother Jonny is likely to start alongside either Ben Toolis or Grant Gilchrist in the second row at the Principality Stadium.
But the younger Gray admits he is disappointed not to be lining up alongside his sibling.
"I'm going to miss him first and foremost," said the Glasgow lock. "It would be great to have him here. It's been a while since I've seen him and I'm absolutely gutted for him.
"Hopefully he can come back soon – I don't think it's something too serious."
Gray's setback is the latest injury blow to befall Scotland ahead of the Championships, with hookers Ross Ford, Fraser Brown and props Zander Fagerson, WP Nel, Darryl Marfo, Allan Dell and Al Dickinson all currently on the casualty list, while tight-head Simon Berghan is suspended for the Cardiff encounter.