Finn Russell has joined up with the Scotland squad and has not been ruled out of Saturday's game against France despite going off with a head injury while playing for Racing 92 on Sunday.
Russell went off before the break against Toulouse and failed the initial head injury assessment.
But he was symptom-free on Monday after arriving in Edinburgh and will undergo further tests to see if he can be back playing in the Six Nations at the weekend after the minimum six-day recovery period.
Scotland forwards coach Danny Wilson said: "Russell is with us in the training group. Obviously it was seen that he didn't meet the criteria to return to the field of play.
"From now on it's an assessment process. Six days from the game is Saturday and there's a process all players go through in that period of time.
"We have just got to go with our experienced and outstanding medical staff."
Full-back Stuart Hogg will not join the squad in the camp this week as he is not being considered to face the French following the shoulder injury sustained against Ireland in the second round.
Head coach Gregor Townsend added six players to the Scotland squad on Monday.
Worcester Warriors stand-off Duncan Weir is joined by Edinburgh trio Magnus Bradbury (back-row), Dougie Fife (wing) and James Johnstone (centre), and Glasgow Warriors front-row forwards Zander Fagerson (tighthead prop) and George Turner (hooker).
The group replaces injured Glasgow Warriors pair George Horne (shoulder) and Stafford McDowall (ankle), as well as front-row forwards David Cherry, Murray McCallum (both Edinburgh) and Jake Kerr (Leicester Tigers).