Scotland duo David Denton and Sean Maitland will miss the start of the Six Nations next month because of injury.
Edinburgh forward Denton, 24, and 26-year-old Glasgow Warriors back Maitland sustained calf and shoulder injuries respectively while playing for their clubs in Europe at the weekend.
Scotland begin their Six Nations campaign in France on 7 February.
A Scotland spokesman said they hoped the pair could be involved later in the tournament after they are declared fit.
Denton had a scan on Monday that confirmed he had torn a calf muscle during Edinburgh's Challenge Cup win over Bordeaux.
Maitland, meanwhile, damaged his shoulder during Glasgow's European Cup loss to Bath.
Castres number eight Johnnie Beattie was added to Vern Cotter's Scotland squad on Sunday in the aftermath of nine injuries over the weekend.
Denton had been the only specialist number eight in the New Zealander's original, 32-man squad.
Edinburgh's Ben Toolis, Dougie Fife, Greig Tonks and Matt Scott also sustained knocks against Bordeaux.
Perpignan forward Alasdair Strokosch also has an injury, while Alex Dunbar joined Glasgow team-mate Rob Harley on the treatment table.