Ruaridh Jackson will not be making his Scotland debut in Sunday's RBS 6 Nations opener against Wales after he was released back to Glasgow.
The 20-year-old fly-half stole the headlines when he was handed his maiden senior call-up when Frank Hadden named his 33-man squad for the match two weeks ago.
Hadden revealed at the time the player - who has made only two Warriors appearances - was more likely to be blooded in the A team before being thrown in at the deep end.
Scotland A’s next match is against Italy A on February 27.
Gloucester scrum-half Rory Lawson has also been released ahead of Wednesday’s announcement of the team to play Wales.
Scotland have two major injury concerns, with Northampton prop Euan Murray and Perpignan lock Nathan Hines both missing training at Murrayfield this afternoon.
Team doctor James Robson said: “We will monitor the progress of Euan (rib) and Nathan (knee) on a daily basis.”
Murray is the biggest concern, with Northampton director of rugby Jim Mallinder saying on Saturday: “Normally, ribs take a few weeks to recover. He is improving, but we don’t know the state.”
Uncapped Glasgow prop Moray Low, who was added to the Scotland squad during last week’s training, remained on national duty today.