Michael O'Neill was pleased to give Kyle Lafferty some much-needed game time after the forward played 80 minutes of Northern Ireland's 1-1 draw against Wales on Thursday.
The visitors looked set for victory in Cardiff thanks to Craig Cathcart's 60th-minute strike, only for Wales to grab a draw when Simon Church won and converted a late penalty.
While conceding so close to the final whistle was disappointing, O'Neill was happy that Lafferty got his first competitive outing since Norwich City's 3-0 FA Cup defeat against Manchester City on January 9.
The forward's lack of action is a worry ahead of Northern Ireland's Euro 2016 campaign, although that should change now he has sealed a loan move to Championship side Birmingham City.
"It would have been nice to win but we were able to give 17 players some game time and experiment with a couple of different systems," O'Neill told BBC Sport.
"Kyle Lafferty got a good 80 minutes under his belt and did well given that he hasn't been playing regularly.
"His loan spell at Birmingham will help him build up his match fitness.
"It was very important for the player as he has had very limited game time and he was up against top-class Premier League centre-backs. We'll have another look at him on Monday night."
O'Neill - who handed a debut to Conor Washington before withdrawing the forward at half time - also took the chance to test out different formations.
Northern Ireland started the game with a back three before switching to a four-man defence for the second half.
"We have very limited opportunities to look at systems but the players adapted to both well," he said.
"Conor Washington was slightly disappointed but he trained well and will be given as much of a chance as everyone else to stake his claim.
"Josh Magennis and Liam Boyce were carrying slight knocks but they will come into contention to play a part against Slovenia on Monday and we will give as many players as possible some game time."
