Alex Bruce and Ben Reeves will play no part in Sunday's Euro 2016 qualifier against Hungary.
The pair are the latest to withdraw from the squad following Ryan McLaughlin's departure due to a knee injury that he picked up in training.
MK Dons midfielder Reeves, who was close to receiving his first cap for the nation, has suffered a hamstring problem, while Hull City's Bruce has left after his wife went into labour.
Meanwhile, Scotland's Graham Dorrans has returned to West Bromwich Albion due to injury, therefore missing Sunday's qualifier against world champions Germany.
