Declan Gallagher and Josh Doig have been called into the Scotland squad ahead of Republic of Ireland's visit to Hampden Park in the UEFA Nations League.
The pair come in as Nathan Patterson and David Turnbull drop out ahead of their games against Stephen Kenny's side and Ukraine.
St Mirren centre-back Gallagher was a key member of the team that qualified for the European Championship and made the squad for the finals but has not played for his country since a Euro 2020 warm-up game against Luxembourg in May 2021.
Hellas Verona left-back Doig has been promoted from the under-21 squad after playing in a friendly win over Northern Ireland earlier on Thursday.
Everton right-back Patterson was wheeled out of Hampden on a stretcher after suffering a knee injury during Scotland's 3-0 victory over Ukraine on Wednesday.
Celtic midfielder Turnbull has failed to shake off an ankle knock.
Follow the Republic of Ireland v Scotland this Saturday (kick-off 7.45pm) via our live blog on RTÉ.ie/sport and the RTÉ News app, watch live on RTÉ 2 and the RTÉ Player, or listen to national radio commentary on RTÉ Radio 1
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