Defender Craig Cathcart and striker Warren Feeney have withdrawn from the Northern Ireland squad to face Norway at Windsor Park on Wednesday.
The pair were part of manager Michael O'Neill's first 24-man squad since taking over from Nigel Worthington, but were ruled out with injuries as the players met up for training in Belfast.
Blackpool's Cathcart, a strong contender to start the match, has a hamstring complaint, while Plymouth forward Feeney failed to overcome a calf problem.
No replacements have yet been named but with the under-21 side not in action this week, O'Neill has several options should he wish to strengthen his squad.
Source: PA
