Dartford have failed in their appeal to overturn the four-match ban handed to Lee Noble, following his sending off against Grimsby in the FA Trophy.
The midfielder was sent off in the 91st minute for violent conduct after clashing with Aswad Thomas.
Manager Tony Burman told BBC Radio Kent: "Looking at the evidence, I thought there was a case to answer.
"The FA disagreed as it wasn't clear enough on the evidence we gave them."
Burman continued: "The referee didn't see the incident, he's purely gone on what the linesman told him.
"He felt that Lee stamped on the player. In the heat of the moment, I feel the referee and the linesman could have dealt with the situation better.
"If anything two yellow cards would have been OK, if that. When I looked at the DVD, Lee has not stamped on him whatsoever.
"The opposing player's leg is up in Lee's groin and taken him off the floor."
Noble will now miss four games, including the second leg of their FA Trophy semi-final against Grimsby, having also been dismissed against Woking in August.
Dartford have a fully fit squad to choose from for the visit of the Mariners, hoping to overturn a 3-0 deficit from the first leg.
Jacob Erskine (knee) and Lee Burns (hamstring) have both recovered from injury to make Burman's squad.
The Dartford boss admitted having to score three goals could actually work to their advantage.
"If it had been 1-0, we'd have said that we'd done the job," he said. "That can have an adverse effect."
"We have got to get those goals back. Football is a strange game and you have to hope things go for you on the day.
"We have 90 minutes to have a go. The players have been consistent and will have a go at Grimsby.
"I now need all the supporters to get behind the boys and give us a good shot."