The 18-year-old joined Dortmund from Genk in the summer. Sascha Schuermann / AFP via Getty ImagesSept. 8, 2026 Updated Sept. 9, 2026 5:34 am EDTBorussia Dortmund’s Konstantinos Karetsas has been taken to hospital after experiencing “circulatory problems” during his side’s Champions League game against Villarreal on Tuesday.The 18-year-old went down with no-one around him shortly after passing the ball, immediately signalling to the Dortmund bench that he needed assistance. He was treated for several minutes, before leaving the Signal Iduna Park pitch on a stretcher in the 27th minute.A statement from Dortmund during the second half of the match said that Karetsas was on his way to hospital.“Konstantinos Karetsas had to leave the field due to circulatory problems,” it read. “Kosta is doing well under the circumstances and is on his way to the hospital for further tests.”
Later on Tuesday night, Dortmund managing director Lars Ricken said: “He felt lightheaded due to circulatory issues. There were no signs of it beforehand. He went to the hospital for further tests. It would be irresponsible to speculate at this point.”Karetsas joined Dortmund from Belgian side Genk in the summer and had started all three of their Bundesliga and Champions League games to open the season, as well as featuring as a substitute in the DFB-Pokal and the German Super Cup.Dortmund have already been struck by injury early in the campaign, with Karetsas’ fellow Greece international Giannis Konstantelias suffering an anterior cruciate ligament tear in his left knee on his Bundesliga debut for the club, having arrived from PAOK in August. That triggered Dortmund’s loan move for Arsenal playmaker Ethan Nwaneri.Dortmund have begun their domestic season with two wins from two and beat Villarreal 3-2 in their Champions League opener. Niko Kovac’s side face Paderborn at home on Saturday.
