O'Neill may turn to his young aces following loss of injured quartet
Michael O'Neill will consider placing his faith in a few of Northern Ireland's Under-21 aces after four senior players pulled out of the panel for tomorrow's friendly with South Korea.
Captain Steven Davis will not add to his 101-cap haul having remained with Southampton due to a hamstring injury that has forced him to miss the Premier League club's last five contests.
Davis was pictured in training with Southampton earlier this week so could be back for Mark Hughes' first Premier League game in charge at West Ham after the international break.
Kyle Lafferty, Niall McGinn and Stuart Dallas all pulled out with injuries too.
Hearts striker Lafferty and Leeds midfielder Dallas have thigh problems while Aberdeen winger McGinn is struggling with a groin issue. All three players have left Northern Ireland to return to their club sides for treatment.
It means O'Neill could turn to the Under-21s to swell his squad for the game with South Korea, but Ian Baraclough's side, who lost to Spain last night, take on Iceland in Coleraine on Monday.
O'Neill explained: "If an Under-21 player or players come in, it won't just be for the experience. It will be because we believe they can contribute as well. They also have a game on Monday so we also have to balance that.
"We'll see how the Spain game goes first before we see how we balance that situation but there is a good chance one or two of the Under-21s will be in the squad, whether that's just on the bench or not.
"Potential game time is hard to say at the minute, though."
One player who could be called into the senior panel is Queens Park Rangers frontman Paul Smyth.
Norwich City left-back Jamal Lewis will be rewarded with his first senior appearance tomorrow, with George Saville and Jordan Jones also expected to start.
O'Neill added: "We had the Under-21s over for dinner the other night and had good fun. I went to have a chat with them at the hotel on Tuesday night with Andy Cousins and Liam Boyce.
"Liam talked to the home-based platers who are in the squad. Coming out of the Irish League slightly later and what he has achieved is a good story for them, for the likes of Gavin Whyte, Ciaron Harkin, Jamie McGonigle and Mark Sykes.
"It's been a good week because it's very rarely we are here together at the one time."
Northern Ireland defender Jonny Evans, who will captain the side in the absence of Davis, is confident the team that almost made it to back-to-back major tournaments will keep improving.
"The Nations League kicks in in September so it is something we will have to get used to," said the West Brom centre-back.
"It's great that the games are competitive and that Michael is still going to be here.
"He has a real hunger and drive about him and wants to push us on to the next level which is good to see.
"They really do give you a lift when young players come in. There is a real impact with the older players.
"Even George Saville coming in at the end of the last campaign and he did fantastically well. Jamal has come in and I've only trained with him two days and he looks like a really top player."