Tooting & Mitcham United manager Jamie Martin has resigned claiming the club's board are putting business before football.
The Scot called time on his three-month stint as Terrors boss after the player budget was cut by a third.
And he fired a parting shot at owner Steve Adkins, claiming he is running the club like a "sitting duck" with no ambition to climb the leagues.
Chairman Bill Hill, who tried to convince Martin to stay, insisted the club’s player budget was still above average in the league.
Mr Hill confirmed that assitant manager Phil Simpson will take charge of the team for this weekend's Ryman League Division One South trip to Whitstable.
Martin also claimed that the impending budget cut was scheduled for the summer but, because the Terrors are unlikely to be promoted or relegated, it was brought forward without fear it would affect the rest of the season.
“I was ready to work with the budget cut in the summer, and I am convinced we could have got into the top four next season,” Martin said.
“But by cutting the budget now, I would lose at least five of my best players and then you’re starting from scratch again.
“I was hoping to meet some middle ground with Bill, but he said there was no room to budge.”
He added: “I have been in professional football and I know this club has the set-up to get into the Blue Square Premier.
“I cannot fault the facilities at Tooting, they are superb, but this is a case of business coming before football.
“I believe Adkins does not have any interest in taking the club forward, he is happy where they are. He does not want to move up because it would mean more wages for players.
“At the moment, this club is just a sitting duck. I had no choice but to resign.”
Mr Hill said: “The club is not going up and it is not going down, and these cuts have to be made to secure our future.
“There are two sides to every story – Jamie wants to build for next season, but in non-League there is no loyalty among players and who is to say they will still be here come next year?”
He added: “I am very sorry to see Jamie go. I wanted him to stay because he has done a great job for us.
“When he took over we were bottom of the table, and now we are in a much better place.”