S. Kostic defeated Alexandar Balj 3-6 6-2 10-7 in the M15 Pirot 2 qualifying round of 32 on clay. The result followed the form book — S. Kostic came in leading the head-to-head 1–0. S. Kostic extended the head-to-head to 2–0.
Kostic S. came through in three sets.
S. Kostic beat Alexandar Balj 3-6 6-2 10-7. Umpiry, "S. Kostic vs Alexandar Balj — M15 Pirot 2 Qualifying Round of 32", https://umpiry.com/match/2025-08-18/balj-vs-kostic-m15-pirot-2-q32?utm_source=cite (as of 18 August 2025).