His United team-mate Stuart Armstrong, former Dundee player Lewis Toshney and St Johnstone striker Stevie May are also included for the European U21 Championship qualifiers against Slovakia and Georgia.
Stark said: "He has hit the ground running and he has grasped the left-back position from the off.
"In the first televised game against Partick Thistle he was impressive.
"We have been keeping an eye on him since then and he has been rewarded by getting in and it has been well-deserved."
Celtic forward Callum McGregor has earned a place in the squad but Tony Watt, on loan at Belgium side Lierse, has been left out due to concerns about his fitness.
"He does need to work on his fitness," Stark said.
"Every time he has come to us he has flagged up that his fitness is not what it should be and it is very difficult for us to gain that fitness.
"I just felt that in the last couple of games, maybe that has shown up a wee bit so we go with ones that are in a good, fit state."
Scotland host joint group leaders Slovakia at St Mirren Park on 10 October before travelling to Tbilisi to face Georgia four days later.
Scotland beat Luxembourg in their Group Three opener in March but lost 4-0 to the Netherlands last month.
Squad to face Slovakia and Georgia:
Goalkeepers: J Archer (Tottenham), C Kettings (Blackpool, on loan to York)
Defenders: S Findlay (Celtic), J Grimmer (Fulham), R Jack (Aberdeen), J McGhee (Hearts), A Robertson (Dundee Utd), C Robertson (Aberdeen), L Toshney (Celtic)
Midfielders: S Armstrong (Dundee Utd), F Fyvie (Wigan), J Herron (Celtic), J Holt (Hearts), L Macleod (Rangers), D McGeouch (Celtic)
Forwards: M Beck (Carlisle), R Fraser (Bournemouth), S May (St Johnstone), C McGregor (Celtic, on loan to Notts County), C Paterson (Hearts)