Central defender Dan-Axel Zagadou has injured the lateral collateral ligament in his left knee in training, Borussia Dortmund have announced.
Dortmund players have been training in small groups as they wait for a date for the Bundesliga season to resume, with football on hold in Germany due to the coronavirus pandemic.
Bundesliga clubs are set to meet on April 23 to discuss a potential return to action, while Zagadou will now begin rehabilitation in a bid to be available to play again this season.
"Over the coming weeks, Zagadou will work intensively with the club's rehab coaches in a bid to return to fitness and – provided the coronavirus pandemic allows for it – help his team in the remainder of the season," a Dortmund statement read.
Zagadou, 20, joined Dortmund from Paris Saint-Germain in 2017. The France youth international has played 13 times in the Bundesliga this season, scoring once.
The defender is regarded as one of the brightest emerging talents in European football and featured in Goal's NxGn list of the best teenage talents in world football in 2018. He hit the ground running when asked to deputise at left-back in place of the injured Marcel Schmelzer at the start of the 2017-18 season.
Second-place Dortmund are four points behind defending Bundesliga champions and leaders Bayern Munich at the moment, with nine matches remaining. They are aiming to win their first domestic league title since the 2011-12 season, when Jurgen Klopp guided them to the championship.
The club were among the first in Europe to announce a return to training following the outbreak of coronavirus, which has shut down top-level football across the continent.
The social distancing rules brought in as a result of Covid-19 prevent clubs from holding full team training sessions, however, Dortmund have had their players working in pairs since the end of last month in order to keep them in shape for when football eventually resumes.
“It’s important that we go back to the field,” Dortmund midfielder and former Liverpool and Juventus star Emre Can said ahead of the resumption of training last month. "It doesn't get boring.”