Aberdeen allowed a two-goal lead to slip from their grasp as they lost 3-2 to Group G leaders PAOK Salonika in the UEFA Europa Conference League.
Goals from Bojan Miovski and Dante Polvara had Barry Robson's men 2-0 ahead at the hour mark at Pittodrie but the Greek side hit back with efforts from Despodov and Vieirinha. The visitors were awarded a penalty in injury time after a VAR intervention and Scwab stepped up to score to give PAOK all three points.
Aberdeen remain third in their section with one point from their opening three matches after Eintracht Frankfurt thrashed HJK Helsinki 6-0 in Germany.
Rangers claimed a 0-0 draw in their UEFA Europa League match with Sparta Prague.
The result leaves both sides on four points after three matches, two points behind group leaders, Real Betis.