Dortmund's Greek talent Karetsas returns to team training after circulation problems

Borussia Dortmund's 18-year-old player Konstantinos Karetsas developed circulation-related health problems following the club's UEFA Champions League match against Spanish side Villarreal. Dehydration has been cited as one of the possible causes, which may have affected the young player during or after the game.

Earlier this week, the Greek footballer resumed individual training sessions, gradually building back up his physical load. He has now joined the team's full training program, suggesting his condition has improved and he is working his way back toward the matchday squad.

Karetsas signed for Dortmund in August, when the Bundesliga club paid around €30 million to sign him from Belgian side Genk. Although he represents Greece's national team, he was actually born in Belgium and previously played for the Belgian U-21 side.

Karetsas is not the only Greek player Dortmund has invested in this transfer window. For a similar fee, the club signed 23-year-old attacking midfielder Giannis Konstantelias from PAOK Thessaloniki. His Bundesliga career got off to a mixed start — he scored on his debut in August but then suffered a serious injury, tearing his knee's cruciate ligament, which has kept him out of action for an extended period.