Borussia Dortmund prospect Konstantinos Karetsas left the field on a stretcher after going down in the first half of the German club's UEFA Champions League contest against Villarreal.
The 18-year-old played a pass but then raised his hand toward the bench and went to the ground. The club's trainers treated him for several minutes, appearing to focus on his upper body. After being stretchered off the field, he went straight to the locker room.
He was replaced by Ethan Nwaneri in the 27th minute.
Karetsas didn't participate in full training with the rest of the team in the day before the match, but manager Niko Kovač said in his pre-match news conference that it was normal for a player or two to complete a gym session rather than be part of the full workout.
He joined Dortmund this summer from Genk, alongside countryman Giannis Konstantelias. Konstantelias suffered an ACL tear in late August, with the Bundesliga club bringing in Nwaneri on loan from Arsenal to help replace him.
This article originally appeared on USA TODAY: Borussia Dortmund prospect Konstantinos Karetsas stretchered off
