The three-time Euros participants have already seen key striker Lyndon Dykes and youthful winger Ben Doak pull out of the squad due to injury, while Andrew Robertson raised alarm bells when he withdrew from a training session earlier this week.
However, the Liverpool man's absence was nothing to stress about, and Clarke is also expecting to have all of Lawrence Shankland, Stuart Armstrong, Scott McTominay and Kenny McLean available following their own precautionary measures.
Shankland's availability should see the Hearts attacker edge out Southampton's Che Adams to spearhead Scotland's 3-4-2-1 setup, where Ryan Christie and John McGinn - the top scorer in the Scottish ranks with 18 efforts - ought to support him.
Having trained normally since his slight scare, Robertson is poised to skipper Scotland from the left wing-back slot, as Celtic's Anthony Ralston bombs down the opposite flank.
McTominay was rested for the recent draw with Finland on June 7 but will undoubtedly return to the XI on Friday, potentially alongside fellow Premier League lynchpin Billy Gilmour as Callum McGregor makes way.
Despite another injury-plagued season, Kieran Tierney remains a stalwart in Clarke's three-man defensive pack, where Jack Hendry and Grant Hanley should also form the wall in front of Angus Gunn.
Scotland possible starting lineup:
Gunn; Hendry, Hanley, Tierney; Ralston, McTominay, Gilmour, Robertson; McGinn, Christie; Shankland