Interim Scotland under-21 coach Ricky Sbragia has named an 18-player squad for the challenge match against Portugal next week.
There are first call-ups for Celtic pair, Stuart Findlay and Marcus Fraser, as well as Rangers midfielder Lewis MacLeod and Hearts forward Callum Paterson. Islam Feruz, who scored a hat-trick for Sbragia's Scotland Under-19s in last month's European under-19 Championship qualifier against Switzerland, has also been included.
Sbragia, in place while Billy Stark takes charge of the senior side for next week's friendly in Luxembourg, told www.scottishfa.co.uk: "I am stepping in as under-21 coach for one match, so having experience of working with many of the players, and staff, does make the transition easier for all of us."
He added: "Players like Stuart Findlay, Marcus Fraser, Lewis MacLeod, Islam Feruz and Calum Paterson have done very well at under-19 level and it is pleasing to see them taking the next step.
"I actually know most of the other players in the squad, having assisted Billy on a few occasions recently, and after taking an under-20 squad to the Netherlands earlier this year.
"It's an exciting squad. Stuart Findlay is a 1995 and has done very well to move through the age groups.
"Lewis MacLeod is a first-team regular for Rangers, Tony Watt is scoring goals for Celtic, and Islam Feruz is another one to watch.
"Billy selected the squad before going on to work with the senior squad. We have spoken in depth about the plans for this match, and it's up to me to carry on Billy's work for now."
Squad: Jordan Archer (Tottenham), Chris Kettings (Blackpool), Kieran Duffie (Falkirk), Stuart Findlay (Celtic), Marcus Fraser (Celtic), Kevin McHattie (Hearts), Clark Robertson (Aberdeen), Lewis Toshney (Celtic), Stuart Armstrong (Dundee United).
Fraser Fyvie (Wigan), Jason Holt (Hearts), Kenneth McLean (St Mirren), Lewis MacLeod (Rangers), Islam Feruz (Chelsea), Dylan McGeouch (Celtic), Callum Paterson (Hearts), David Smith (Hearts), Anthony Watt (Celtic).