Marco Reus will be sidelined for at least four weeks after suffering a muscle injury in Borussia Dortmund's DFB-Pokal loss to Werder Bremen on Tuesday.
Lucien Favre's side were beaten 3-2 by the Bundesliga strugglers as Reus was forced off in the closing stages of a damaging evening for the visitors.
Dortmund tweeted on Wednesday to confirm their captain would not be fit to return to training until next month, ruling him out of the Champions League clash with Paris Saint-Germain on February 18.
"Captain Marco Reus contracted a muscle injury in the DFB-Pokal," the tweet read.
"According to the current status, he will be able to start training again in around four weeks."
That timeframe would rule the attacking midfielder out of the next four top-flight matches, but he could be back in the reckoning for the trip to Paris on March 11.