Midfielder Jonathan Douglas today became the latest player to withdraw from the Don Givens' Republic of Ireland squad due to injury.
The caretaker manager is to wait until Thursday before deciding whether to call up any additional players.
Late additions Darren O'Dea of Celtic and Ipswich Town's Alex Bruce joined up with the squad at their base in Wales earlier today and took full part in training.
Paul McShane and Stephen Hunt - who are both carrying knocks - sat out the session as a precautionary measure.
Goalkeeper Shay Given was scheduled to join up with the squad later this evening.
Ireland face Wales in Cardiff on Saturday in the final game of their ill-fated Euro qualification regime.