Conor Bradley played for Liverpool's Under-18 team in their FA Youth Cup defeat by Aston Villa on Monday
Chelsea's Sam McClelland and Liverpool's Conor Bradley have been handed first senior Northern Ireland call-ups for the friendlies against Malta and Ukraine.
Centre-back McClelland, 19, has played for the Northern Ireland U17s and U19s.
Bradley, 17, has also featured for the U17s and played in Liverpool's FA Youth Cup Final defeat by Aston Villa earlier this week.
Steven Davis and Jonny Evans are among the experienced players rested.
Corry Evans, Conor McLaughlin, Jamal Lewis, Michael Smith, Michael McGovern and Trevor Carson will also not be involved in the behind-closed-doors match against Malta in Austria, which has been brought forward from Monday to Sunday, and next Thursday's game in Ukraine.
The Irish FA said that Fifa regulations mean the Malta game will kick off at the Worthersee Stadium in Klagenfurt at 17:00 BST with the Ukraine match in Kyiv, which will also be behind-closed-doors, starting on 3 June at 19:00.
Northern Ireland's squad includes Stuart Dallas, Paddy McNair, Kyle Lafferty, Josh Magennis, Craig Cathcart and Niall McGinn.
Sam McClelland is a regular in Chelsea's Under-23 team
Baraclough's 'fast-tracking' plans
Manager Ian Baraclough said the inclusions of McClelland and Bradley were part of his "fast-tracking" plans.
"Conor's had a really good season with Liverpool – his first year there – he's played regularly in the U23s and was in the FA Youth Cup final the other night," added the Northern Ireland boss.
"We just feel his development has been has been very, very good this season. And to give him the knowledge of what it's like with this group, we thought it was the right time.
"With Jonny [Evans] not here and Dan Ballard involved with the play-off final with Blackpool as a centre-half, we felt it was the right time to bring Sam through. And again, let's see what is what is what he's about as an individual."
Baraclough said that he had told senior players in March that they could opt out of the two friends.
"I realise it has been back-to-back for two seasons with no break – invariably two games a week. That's tough.
"Within a bubble, with all the coverage, restrictions of travel, being away from your families as well for long periods, I realise that this trip wasn't for everybody."
Rangers winger Jordan Jones and Paul Smyth, whose contract with QPR is about to expire, both return to the squad with Linfield's Shayne Lavery, Accrington Stanley striker Dion Charles, who made his debut against the USA, Manchester United's Ethan Galbraith and Leeds United's Alfie McCalmont also among those who will take part in the tour.
Liverpool keeper and Bradley's club-mate Liam Hughes retains his place in Ian Barcalough's squad after earning a first call-up for the games against Italy, USA and Bulgaria.
Northern Ireland squad
Goalkeepers: Peacock-Farrell (Burnley), Hazard (Celtic), Hughes (Liverpool).
Defenders: Cathcart (Watford), Dallas (Leeds United), Ferguson (Millwall), McNair (Middlesbrough), Ballard (Arsenal – on loan at Blackpool), Brown (Cardiff City), McClelland (Chelsea), Bradley (Liverpool)
Midfielders: McGinn (Aberdeen), Saville (Middlesbrough), Thompson (Stoke City), McCann (St Johnstone), McCalmont (Leeds United), Jones (Rangers), Whyte (Cardiff City), Galbraith (Manchester United)
Forwards: Lafferty (Kilmarnock), Magennis (Hull City), Boyce (Heart of Midlothian), Lavery (Linfield), Charles (Accrington Stanley), Smyth (Queens Park Rangers).
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