Next weekend's clash between QPR and Swansea City has been plunged into doubt after the Hoops' Monday night game against Sheffield United was postponed due to a Covid outbreak at the London club.
Russell Martin's are set to head to West London on Saturday, but news of the cancellation of the Bramall Lane fixture will now put that weekend game in jeopardy.
QPR have told the EFL that there have been "several" positive cases within their camp and that they do not have the numbers required to keep the game on as scheduled.
In a statement, the London club wrote: "Monday's Sky Bet Championship fixture between Sheffield United and QPR has been postponed.
"QPR have informed the EFL that, following several positive COVID-19 tests among our players and staff, we have insufficient numbers to fulfil the fixture.
"The circumstances surrounding the postponement will now be the subject of an investigation in accordance with EFL regulations. A rearranged date for the fixture will be announced in due course.
"We apologise for any inconvenience caused and will update supporters with further information as soon as it is available."
The EFL added: "In accordance with EFL Regulations, the League will now review the circumstances surrounding the postponement with a rearranged date for the fixture to be confirmed in due course."
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