Scotland’s injury problems continue to mount, with goalkeeper Angus Gunn ruled out of the Nations League matches against Croatia and Portugal.
The 28-year-old took a knock to the ribs and was withdrawn at half-time during Norwich City’s win over Hull City on Saturday.
Gunn’s absence makes a return for veteran Craig Gordon likely.
Kilmarnock’s Robby McCrorie has been drafted in and joins fellow uncapped keeper Jon McCracken in Steve Clarke’s squad.
There is also a first call up for Aberdeen left-back Jack MacKenzie, 24, to replace Greg Taylor.
The Celtic defender is recovering from a calf problem sustained in last week’s Champions League defeat by Borussia Dortmund.
MacKenzie’s Pittodrie team-mate Nicky Devlin had already received a first call, along with Preston centre-half Liam Lindsay and West Ham midfielder Andy Irving.
Gunn and Taylor take the tally of unavailable players to 12, including influential vice-captain John McGinn.
Gordon, 41, was included by Clarke after being cut from the Euro 2024 squad.
The Hearts goalkeeper, who made his international debut 20 years ago, earned his 75th cap as a substitute in the final warm-up game for the summer tournament.
Scotland visit Zagreb on Saturday before hosting Portugal three days later.
Portugal lead Group A1 on six points, with Croatia and Poland both on three and Scotland yet to get off the mark.
