Rotherham's Championship game with Middlesbrough became on Wednesday the latest match to be postponed due to coronavirus after the second tier side informed the English Football League that some of their players had tested positive.
Rotherham's previous match against fellow strugglers Derby County was postponed due to one case of Covid-19 in their squad.
However, on Wednesday they issued a statement saying they could not play Middlesbrough on Saturday as other players had contracted the virus.
Fellow second tier side Millwall had announced on Monday they would be postponing their next two matches due to several playing staff testing positive.
"Following a number of further positive cases of Covid-19 confirmed last night (Tuesday) within the Rotherham United first-team squad, we have reluctantly -- but with the safety of our players and staff at the forefront of our minds -- informed the EFL and our opponents, Middlesbrough, that we will be unable to fulfil our Boxing Day (Saturday) fixture," read their statement.
The club added they hoped to make a decision on future fixtures later on Wednesday.
The EFL will now look into the matter, with rearranged fixtures set to be confirmed "in due course".
The EFL, though, have been criticised for not conducting testing often enough.
Paul Lambert manager of third tier Ipswich told the BBC the scarcity of Covid-19 testing in the EFL is "putting people's lives at risk" after he tested positive for the virus.
Lambert is one of eight people at the club to have had a positive Covid test and as a result they have postponed their next two matches.
The EFL has competition-wide testing at different times throughout the season with the next round scheduled for the week commencing January 4.
"It's the protocols that have worried me more than anything else," said Lambert on Tuesday.
"I think you're putting people's lives at risk by not getting them tested regularly. It's been shocking.
"I know friends in Bundesliga 3, which is the equivalent of League One, and they've been tested over 50 times since they've been back in pre-season.
"Without our owner (Marcus Evans), who has paid for two out of his own pocket, we'd have been down to about six testings which is nowhere near enough."
Prior to Lambert's comments, the EFL said it would be "reviewing and strengthening" coronavirus protocols over the festive spell "to help minimise transmission risk" and that players and staff showing symptoms would continue to be tested.