Chris Brunt and Sammy Clingan are the latest players to have withdrawn from the Northern Ireland squad for Tuesday's Euro 2012 qualifier against Italy.
An ankle injury has forced West Bromwich Albion midfielder Brunt to pull out, while Coventry City's Clingan has a back problem.
The pair have joined Lee Camp and Grant McCann on the sidelines, while Kyle Lafferty is suspended.
Jonny Evans is also missing for Nigel Worthington's men with an ankle complaint.