Hibernian defender Paul Hanlon has been called into the Scotland squad.
Hanlon comes in as defensive cover after Scotland lost Liam Cooper and Andy Robertson in recent days.
Cooper returned to Leeds ahead of Sunday's 1-0 win over Slovakia as 33-year-old Aberdeen defender Andy Considine made his debut.
Robertson picked up a suspension for Wednesday's visit of the Czech Republic after being booked for kicking the ball away.
Hanlon, 30, has been named in a squad before but is yet to be capped, although he appeared 23 times for the under-21s.
The centre-back joins fellow Hibs defenders Ryan Porteous and Paul McGinn in the squad.
Clarke also lost Scott McKenna, Liam Palmer and Kieran Tierney from his defensive ranks before last week's Euro 2020 play-off win over Israel.
