The Professional Footballers' Association has been called in to offer advice after Sheffield Wednesday failed to pay its players on time.
It is understood the Championship club's players only received a percentage of their November salaries.
And they met with club officials on Wednesday to discuss the situation.
The news comes at a difficult time for the Owls, who are bottom of the table after a six-point deduction and poor results under new boss Tony Pulis.
Wednesday have collected three points in eight games under Pulis and are yet to win a match since he took charge on 13 November.
They are now seven points adrift of safety, meaning they would still be in the relegation places even without the six-point deduction for breaching spending rules that was applied in November, which was in itself reduced from 12 points.
However, while it is understood the EFL is yet to be officially notified of the situation, it does has the power to impose a transfer embargo if they deem it appropriate, which would potentially prevent Pulis bringing in new players during next month's transfer window.
It is the second time this year there has been a problem with Wednesday players being paid their wages after some did not receive the full amount in June, although that issue was later resolved.