Deportivo La Coruna fear they could enter administration before the end of the month.
A side which lifted the Primera Liga title in 2000 is reported to owe the taxman around 34million (£27.7m), and have total debts of 100million (£81.4m).
The Spanish government are looking to crack down on outstanding tax bills and have hit Depor with an embargo on their income.
Club president Augusto Cesar Lendoiro claims efforts to try and resolve the situation are under way, but concedes that administration is a distinct possibility.
"Either we reach an agreement with the tax authority before the end of the year or we go into administration. We cannot wait any more," he said.