Kostic has been ruled out of the tournament after sustaining a knee injury in Serbia's 1-0 defeat to England in their opening group fixture last Sunday.
Filip Mladenovic replaced Kostic on the stroke of half time in that match and he is seemingly the most likely candidate to be handed a start at left wing-back, with Andrija Zivkovic set to continue on the opposite flank.
Strahinja Pavlovic was run ragged by England's Bukayo Saka last time out, but the Red Bull Salzburg defender should keep his spot on the left side of a back three next to Nikola Milenkovic and Milos Veljkovic.
Fulham's Sasa Lukic and Sevilla's Nemanja Gudelj are set to continue in centre-midfield, unless manager Dragan Stojkovic decides to move Sergej Milinkovic-Savic into a deeper role after starting as a number 10 against England.
Should Milinkovic-Savic play deeper, that would open the door for playmaker Dusan Tadic, who surprisingly began as a substitute against England and made an impact off the bench, to return to the first XI and link up with attacking duo Aleksandar Mitrovic and Dusan Vlahovic up front.
Serbia possible starting lineup: V. Milinkovic-Savic; Veljkovic, Milenkovic, Pavlovic; Zivkovic, S. Milinkovic-Savic, Gudelj, Mladenovic; Tadic; Vlahovic, Mitrovic
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