Matt Phillips and Phil Bardsley have pulled out of the Scotland squad for this week's friendly with Slovenia through injury.
Blackpool winger Phillips has a hamstring injury while Sunderland full-back Bardsley has a suspected tear in his calf.
The news is a blow for Phillips after he earned his first call-up to the Scotland squad last week for the Slovenia game.
The pair join Celtic midfielder Scott Brown in pulling out of the squad.
Wigan midfielder James McArthur was added after Brown withdrew over the weekend but no-one else has been called up by Craig Levein.
Scotland assistant manager Peter Houston confirmed they were unlikely to draft anyone else into the squad despite the withdrawals.
"Phil was here last night," Houston said. "Matt Phillips is still here but they're not going to make it.
"At this moment in time nobody has been brought into the squad."
Carling Cup trio
Meanwhile, all three of the players who played in the Carling Cup final have confirmed they will join up with the squad.
Cardiff pair Don Cowie and Kenny Miller were on the losing side while Liverpool midfielder Charlie Adam claimed a winner's medal despite missing a penalty in the 3-2 shoot-out victory, which followed a 2-2 draw.
Houston revealed manager Levein had spoken to Cardiff boss Malky Mackay after the game.
"We spoke to big Malky last night and the guys are keen to come," Houston added.
"Kenny Miller, at the age he is at (32), is still keen to come.
"They might not make this afternoon's training session but they will do a recovery session with the physios."