Scott McKenna, who had proved an able deputy at left centre-back during the continued absence of Arsenal’s Kieran Tierney, is an almost certain absentee with a hamstring injury that forced him to miss Las Palmas’ draw with Real Betis.

With Al Ettifaq’s Jack Hendry and Bristol City’s Ross McCrorie having not played for their clubs yet this season, and Ryan Porteous and Grant Hanley both weekend substitutes for Championship sides Watford and Norwich respectively, it leaves Clarke with few centre-half options who are starting for their clubs.

Liam Cooper at least played the full 90 minutes of his debut for mid-table CSKA Sofia in their 0-0 draw away to third-top Cherno More after his move from Leeds United to Bulgaria was held up by red tape.

The lack of options has led to a report suggesting Clarke is considering a first call-up for 28-year-old Liam Lindsay, despite Preston North End sitting third bottom of England’s second tier.

Similarly, at right-back, Nathan Patterson has only just returned to action with Everton’s reserves, while Anthony Ralston was unused on Celtic’s bench

Max Johnston started a 2-1 win away to Blau-Weiss Linz that took Sturm Graz to the top of the Austrian Bundesliga, but he is one of several young players Clarke has to decide whether would be better deployed helping the under-21s in their crucial European Championship qualifiers.