Flyhalf Finn Russell will miss Scotland's Six Nations opener against Ireland for disciplinary reasons, Scottish Rugby said on Thursday.
It was unclear whether the 27-year-old would feature in the rest of the campaign.
"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," Scottish Rugby said in a statement.
"He has returned to his club."
The BBC said it understood Russell, who plays for French side Racing 92, had left the training camp in Edinburgh of his own accord.
The departure of one of the side's most creative players adds to the pressure on coach Gregor Townsend after a failed World Cup campaign last year in which the Scots crashed out at the pool stage after defeats to Ireland and hosts Japan.
Scotland play their opening game at Dublin's Aviva Stadium on Feb 1.
(Reporting by Alan Baldwin, editing by Toby Davis)
