Livingston's on-loan teenager Bobby Burns is in Northern Ireland's senior squad for matches against the Republic of Ireland and Austria.
The 19-year-old has been rewarded for an impressive first season in full-time football having left Irish Premiership side Glenavon in the summer.
The defender, who can also play in midfield, signed for Hearts before moving to Livingston on loan.
Northern Ireland play the Republic in a friendly in Dublin on Thursday.
Burns played the full game as Livingston frustrated Scottish Premiership champions Celtic in a 0-0 draw on Saturday.
The Belfast native emerged as a key player for Gary Hamilton's Glenavon last season and impressed while playing in numerous positions ranging from left-back to striker, contributing eight goals and 12 league assists.
Hearts moved for the then 18-year-old in May as Burns signed a three-year deal with the Tynecastle side.
"He obviously played very well for Livingston against Celtic and he will join us on Monday," said manager Michael O'Neill.
He is the fourth player to have been called up after impressing in Ian Baraclough's Under-21 squad in the European qualifying campaign, where they finished second behind a Spain side they shocked 2-1 in Albacete.
Celtic goalkeeper Conor Hazard, QPR winger Paul Smyth and Blackpool midfielder Jordan Thompson have all previously featured in senior international friendlies but are yet to play a competitive fixture.
Although relegation to the third tier of the Nations League looks likely, Northern Ireland will hope to end their campaign with a first win in the new tournament against Austria on Sunday.
Northern Ireland squad
Goalkeepers: Michael McGovern (Norwich City), Trevor Carson (Motherwell), Bailey Peacock-Farrell (Leeds United), Conor Hazard (Celtic).
Defenders: Aaron Hughes (Hearts), Gareth McAuley (Glasgow Rangers), Jonathan Evans (Leicester City), Craig Cathcart (Watford), Conor McLaughlin (Millwall), Patrick McNair (Middlesbrough), Jamal Lewis (Norwich City), Michael Smith (Hearts), Tom Flanagan (Sunderland), Bobby Burns (Livingston, loan).
Midfielders: Steven Davis (Southampton), Niall McGinn (Aberdeen), Corry Evans (Blackburn Rovers), Shane Ferguson (Millwall), Stuart Dallas (Leeds United), George Saville (Middlesbrough, loan), Jordan Jones (Kilmarnock), Gavin Whyte (Oxford United), Jordan Thompson (Blackpool).
Forwards: Kyle Lafferty (Rangers), Josh Magennis (Bolton Wanderers), Jamie Ward (Charlton Athletic, loan), Liam Boyce (Burton Albion), Paul Smyth (Queens Park Rangers), Kyle Vassell (Rotherham United).