Sheffield Wednesday have closed their Middlewood Road training ground due to a coronavirus outbreak, the PA news agency understands.
The Sky Bet Championship club, who sacked manager Tony Pulis last week, have declined to comment on the number of squad and staff members affected.
Players are expected to train at home for the next two days, while it is hoped the training complex can reopen later this week with further Covid-19 tests scheduled for Wednesday, it is understood.
First-team coach Neil Thompson has been placed in temporary charge of the Owls, who are due to face Exeter away in the FA Cup third round on Saturday.
The club's 12-point deduction for breaching financial regulations was reduced to six points on appeal by the English Football League in November.
Wednesday have won both their games under Thompson since the departure of Pulis and have taken 10 points from their last four games.
The Owls climbed out of the relegation zone for the first time this season after Friday's 1-0 home win against Derby.