Hannover defender Timo Hubers has tested positive for coronavirus, the 2. Bundesliga side have confirmed.
The club believe the 23-year-old contracted the virus at an event in Hildesheim on Saturday.
In a statement released on Wednesday, Hannover said Hubers immediately self-isolated after going to the doctor for tests once he had learned he had been in contact with someone who had the virus.
They believe it is unlikely Hubers could have passed the infection to the rest of the squad as he has not been in contact with them since last Saturday. However, as a precaution, all Hannover players and staff will be tested.
Sporting director Gerhard Zuber said Hubers behaved in "absolutely exemplary" fashion.
"He has himself shown no symptoms up to now," said Zuber. "When he found out that a person who had been with him at the event had tested positive, he reported directly to the doctor and temporarily went into quarantine at home."
Hubers will not be considered for Sunday's league match with Dynamo Dresden, but the rest of the team is preparing as normal, Hannover said.
However, all media and PR activities have been cancelled "for the time being" and the game is one of several in Germany this week that will be held behind closed doors.
Hannover sit ninth in Germany's second tier after 25 matches this season.