A makeshift Northern Ireland XI drew 1-1 with Qatar on Sunday and Michael O'Neill is yet to decide who will start versus Romania next month.
Michael O'Neill indicated his decision as to who starts in Northern Ireland's Euro 2016 qualifier against Romania next month will be determined by the fitness of his players.
An inexperienced Northern Ireland side draw 1-1 against Qatar at Gresty Road on Sunday, as Stuart Dallas' opener was cancelled out by Karim Boudiaf's long-range curling effort in the 70th minute.
The bigger challenge comes on June 13, though, as Group F leaders Romania visit Belfast in a top-of-the-table European Championship qualifier.
Northern Ireland impressed in their last pool fixture by beating Finland 2-1, but manager O'Neill warned that the players who featured in that game are not guaranteed to keep their place.
"My team will not necessarily be based on the team that beat Finland but who is most ready to play in terms of when the game occurs," O'Neill said.
"Fitness levels and intensity in training will show who is game ready."
Reflecting on the match against Qatar, O'Neill felt there was plenty for him to be pleased with.
"There were plenty of positives to take from the game - a lot of our players are in the infancy of their club careers and are being asked to make the step up to play international football," he added.
"I was delighted with a lot of aspects of our play and I thought we played really well for 60 or 65 minutes.
"The pitch was a little bit difficult but we tried to play some good football. We could just have taken more care with our final ball in the first half.
"We didn't turn the possession we had into opportunities as well as we could have but we did well considering that some of those lads haven't played a game in the best part of a month."