Borussia Dortmund have released a statement after one of their players had to be stretchered off the field and sent immediately to the hospital from their Champions League clash

Borussia Dortmund star Konstantinos Karetsas has been taken straight to the hospital after being stretchered off the field in their Champions League clash against Villarreal. The Bundesliga side have revealed that Karestsas suffered a 'circulation problem'.

The Greece international, 18, went down without a challenge from the opposition, sitting down on the turf. He raised his arm to call for treatment, having moments before dribbled and played a pass with no problem.

Karetsas, who joined Dortmund from Genk in the summer, was making his fifth appearance for the club. The shocking scenes will have caused plenty of alarm, but the German club have indicated he is doing as well as can be expected.

Dortmund said in a statement: "Konstantinos Karetsas had to leave the pitch in the game against Villarreal due to circulation problems. Kosta is doing as well as can be expected given the circumstances, and he is on his way to the hospital for further examinations."

There was consternation on the sidelines, with former Dortmund ace Mats Hummels, working as a pundit on Prime Video, highlighting his concern.

"When the doctors did not look at his legs at all and were only focused on his upper body, it sent a shiver down my spine," he said. "We would not wish something like that on anyone. Those are really horrible scenes we had to see there."

Karetsas was replaced by Arsenal loanee Ethan Nwaneri with just 27 minutes played in Dortmund. They were able to overcome their concern to take the lead against the Yellow Submarine after half-time as Renato Veiga turned the ball into his own net.

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Villarreal got on level terms after 66 minutes when Santiago Mourino got on the scoresheet. But Dortmund were able to make their pressure tell as Serhou Guirassy scored in the 80th minute to restore their advantage, and the same player scored from the penalty spot five minutes later to give the home side an unassailable lead.

Dortmund did receive a scare when Guirassy knocked the ball into his own goal in the 93rd minute. The Bundesliga team were able to hang on to earn three points.

There were also surprising scenes at the Westfalenstadion, with only 39 Villarreal fans turning up to enter the away section for the Champions League match. Dortmund had to close a 4,000-seat section due to the short notice when they learned of the situation.