The 32-year-old has undergone surgery on his adductors after experiencing recurring problems in the area during rehabilitation from a serious knee injury, according to German reports.
The procedure was successful, but there is currently no clear timetable for Can's return. Bild reports that the defender is unlikely to feature for Dortmund again this year, with a return to full team training not expected until January at the earliest.
Can has been recovering from a torn posterior cruciate ligament in his left knee, sustained during Dortmund's home match against Bayern Munich on February 28.
The Germany international had been working towards a comeback and was reportedly continuing his rehabilitation at Dortmund's training ground during the recent international break before the latest setback.
Despite his prolonged absence, Can remains an important figure at Dortmund. The club extended his contract in March until June 2027, while he has also continued to support teammates during their own injury recoveries.
Nico Schlotterbeck, who has been working his way back from injury himself, previously praised Can's support during his rehabilitation.
"He accompanied me and was supporting me, because he's simply an incredible guy," said Schlotterbeck, who could make his return against Bodø/Glimt on Wednesday.
Dortmund had made clear from the outset that they would stand by their captain during his recovery.
"He is our captain, always puts himself at the service of the team and is an important part of our club. Emre will receive every support from us over the next few months so that he can make a full recovery," said then-sporting director Sebastian Kehl.
For now, however, Can faces another lengthy period of rehabilitation before he can return to competitive action.
