Darren O'Dea has been forced to withdraw from the Republic of Ireland squad ahead of Tuesday's match against Andorra.
Giovanni Trapattoni had been hopeful of going into the Republic's second Euro 2012 qualifier without losing any more players.
However, Ipswich defender O'Dea has now returned to his club for treatment after being ruled out with a knee problem.
The 23-year-old last week underwent a scan, which revealed a slight sprain, and although he was included in the party which flew out to Yerevan last Wednesday, he did not make the 18 for the 1-0 victory over Armenia.
O'Dea was able to train at Gannon Park in Malahide on Sunday, but it has since been decided that he should not be risked.
He becomes the fourth member of the squad to pull out, following Damien Duff, Keith Andrews and Keith Treacy on to the sidelines.
A fifth casualty, Paul McShane, is back in training after recovering from the hamstring problem which prevented his participation in Armenia.
Having secured a hard-fought win in their opening match, assistant manager Marco Tardelli is targeting another three points against Andorra.
The European minnows will not be expected to provide much resistance away from home, but Tardelli has told his men not to take anything for granted.
He said: "Normally, it is possible to win against Andorra, but you know football. Everything is possible on the pitch.
"Yesterday, I saw the DVD of the game against Russia and they played well. Andorra had two chances to score.
"Every match is difficult. We respect Andorra. We respect every team, but normally it is possible to win."