Barnsley's game at home to Stoke City on Wednesday has been postponed due to Covid-19 cases at Oakwell.
The Reds have several players and two coaches isolating after testing positive for the virus, while at least five first team players are out injured.
The EFL have allowed teams to postpone games if they have fewer than 14 first team players available.
The Reds were down to the bare bones for Saturday's FA Cup win over Barrow, with four under 23s players on the bench and only seven of nine possible substitutes.
The match was originally due to take place on Boxing Day but was postponed due to the Potters' Covid cases.
A Barnsley statement read: "The club has worked hard to ensure that it has been able to fulfil the fixture.
"However, taking into account the number of injuries and positive COVID-19 cases with the squad, the club does not have a sufficient number of players available in order to fulfil the fixture."We apologise for the inconvenience of this postponement, and details regarding the rearrangement of the fixture will be communicated to our supporters in due course."