Millwall's next two Sky Bet Championship fixtures have been postponed due to a coronavirus outbreak in the first-team squad.
Games against Bournemouth and Watford over the Christmas period will now be played at a later date while the club's training ground has been closed.
A club statement said: "Millwall Football Club can confirm that its next two Championship fixtures have been postponed following an outbreak of Covid-19 within the first-team squad.
"Individuals who have tested positive and their close contacts are observing a period of self-isolation and the club cannot therefore currently take part in upcoming fixtures", which are away to AFC Bournemouth on 26 December and at home to Watford on 29 December.
"The club's Calmont Road training ground has been closed with immediate effect in order to protect players and staff and to help prevent further spread of the virus."
Millwall chief executive Steve Kavanagh added: "This is a very regrettable but necessary move.
"Throughout this entire pandemic the safety and welfare of our players, staff, fans and other stakeholders has been our main priority and it is with this in mind that we have closed the training ground and notified the EFL of the need to postpone the next two fixtures.
"I wish everyone concerned a quick and full recovery."