Achraf Hakimi has been ruled out for the rest of the season after suffering a broken metatarsal in Borussia Dortmund's 2-0 win over Wolfsburg at the weekend.
The full-back – on loan from Real Madrid – came on as a substitute to replace the injured Abdou Diallo in the 49th minute but then had to be replaced himself with 16 minutes remaining.
He will now miss the club's remaining Bundesliga fixtures – including Saturday's pivotal clash against title rivals Bayern Munich – and faces a race to be fit for Morocco's Africa Cup of Nations campaign.