Wednesday 11 November 2015 08:27, UK
Chris Brunt is out of Northern Ireland's friendly against Latvia on Friday evening.
Michael O'Neill told Sky Sports News HQ Brunt has remained with West Brom for treatment on an ongoing, but unspecified, problem.
Manchester United defender Paddy McNair, left out of the initial squad because of an abdominal injury, has been called up to the squad but will play no part in the game.
Northern Ireland host Latvia in Belfast in their first game since qualifying for next summer's Euro 2016 finals.
And O'Neill said: "It's great for the players to get the recognition they've had - they're enjoying it, but they're focused again and we're back on the training pitch again.
"There's possibly an opportunity to look at a few things, a change in the system - we don't have that many games before the finals so we've got to think about our preparation."
Northern Ireland squad: Carroll, Mannus, McGovern, Baird, McAuley, J Evans, Cathcart, Ferguson, Hodson McLaughlin, McNair, Davis, C Evans, Norwood, McCourt, Dallas, Lafferty, McGinn, Ward, Magennis, McKay, Grigg, Boyce.
