Borussia Dortmund face fresh injury concerns surrounding Greek international Konstantinos Karetsas following Saturday afternoon’s goalless Bundesliga draw away at Union Berlin. The 18-year-old, who has only recently returned to action following a worrying medical episode in September, suffered an apparent ankle injury just eight minutes after entering the match as a substitute.

Karetsas was attempting to shield the ball from Union midfielder Rani Khedira inside Dortmund’s penalty area when he awkwardly twisted his right ankle. The attacking midfielder immediately went down in pain, prompting teammate Nico Schlotterbeck to signal for another substitution. Karetsas subsequently required assistance from the club’s medical staff as he limped off the pitch.

According to Kicker , the precise nature and severity of the injury remained unclear immediately after the final whistle. Dortmund must now await further examinations to determine whether another spell on the sidelines will be necessary.

Speaking to Sky Germany before Saturday’s match, Dortmund head coach Niko Kovac had already explained why Karetsas would begin the afternoon on the substitutes’ bench.

“I’m watching the lad, and he’s not yet where he was before,” Kovac acknowledged.

Kovac was referring to the frightening incident during September’s Champions League victory over Villarreal, when Karetsas collapsed after experiencing circulatory problems and required hospital treatment.

The summer signing was subsequently discharged from hospital , although further medical examinations were necessary before Dortmund could contemplate his return. Kovac suggested that the incident might still be weighing on his young attacker.

“We can all still remember what happened when Kostas collapsed during the Champions League match,” the BVB trainer explained. “I think that’s still in the back of his mind. We can’t disregard that.”

From a tactical formation and squad depth perspective, "Borussia Dortmund’s Konstantinos Karetsas suffers fresh injury blow amid already difficult recovery path" carries substantial tournament implications for international seeding and domestic campaign momentum. Coaching staffs are heavily weighing high-pressing efficiency (PPDA), defensive transition pace, and fixture fatigue management.

Tactical analysts monitoring Champions League metrics emphasize that squad adaptability and set-piece execution will likely dictate outcomes in high-leverage knockout environments. Real-time match telemetry and tracking data continue to inform managerial decision-making.

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