West Ham manager David Moyes, along with players Issa Diop and Josh Cullen, were forced to pull out of their side’s victory over Hull City due to returning positive tests.
The Tigers refused tests themselves, despite West Ham offering to pay for them, with manager Grant McCann insisting the League One club were following EFL guidelines – with clubs below the Premier League not obliged to do tests on staff this season.
It angered West Ham co-owner David Sullivan, who said Premier League clubs are coming up against sides who are not being tested regularly enough.
He said: “Medically, why are we in a competition where we’re playing teams who have not been checked? The EFL are not testing their players for financial reasons.”
The Sun report that top-flight clubs will threaten to pull out of the Carabao Cup unless the issue is resolved.
Sullivan added to talkSPORT: “We and a few other Premier League clubs made the offer to give these teams a test at our expense so we weren’t exposing our players to untested players.
“Unfortunately, Hull didn’t want it. Charlton the previous week did, for example.”
An outbreak at League Two club Leyton Orient was detected when the club took Tottenham Hotspur up on their offer to pay for testing.
The game was subsequently called off, with Spurs expected to be granted a bye to the next round.
A round of testing costs £5,000 per club, with Premier League sides continuing to test players once a week.
It led to Orient missing out on vital revenue by not hosting Spurs and chairman Nigel Travis admits that, in hindsight, testing his players actually proved to be a mistake.
He said: “If I was doing this again I would not do the testing.
“This is an incentive not to test.”