Finn Russell could miss the whole of the 2020 Six Nations campaign after the fly-half was sent home from Scotland's training camp ahead of the tournament opener.
Gregor Townsend's side face Ireland in Dublin on February 1, but will do so without the influential stand-off after a breach of team protocol.
Russell has been disciplined as a result, and has returned to club side Racing 92 in Paris.
A statement from a Scottish Rugby spokesperson read: “Stand-off Finn Russell will play no further part in preparations for Scotland’s Six Nations opener against Ireland, having been disciplined for a breach of team protocol during the week’s camp in Edinburgh.
"He has returned to his club."
There has been no comment on whether Russell, who has accrued 46 caps for Scotland since making his debut in 2014,l will rejoin the squad after the Ireland clash.