Ebbsfleet United have appealed to the Football Conference against a decision not to allow them to sign another goalkeeper.
First-choice Preston Edwards is injured, while Gillingham youngster Daren Hawkes (pictured) is the only other option.
The Fleet play the second leg of their play-off semi-final against Chelmsford at Stonebridge Road on Sunday.
Ebbsfleet manager Liam Daish said: "I think it is unfair. Every team should have two keepers available for the play-offs with so much at stake – all your hard work could be wasted.
"If something happened to Daren, we would be stuck without a keeper and it makes it a bit of a farce.
The Fleet boss wants a big crowd to get behind them at the weekend and help them toward their target of an immediate return to the Blue Square Bet Premier.
He added: "We want as much support as we can get to give the lads a real boost and help us hopefully do what is required. It was a real team effort at Chelmsford. There were no weak links and in the end, a bit of quality showed through."
The game on Sunday kicks-off at 3pm, with the final the following week at the ground of the highest-placed finalist.