Derek Pope quit as chairman of Havant & Waterlooville directly after Saturday's dire 3-0 home defeat by Newport County.
Having started the season with high hopes of winning the Dr Martens Premier Division title, the slip-sliding Hawks - down to 11th in the table - could now struggle to achieve even the top-half finish required for Conference 2 football next season.
Poor results have heaped pressure onto joint managers Liam Daish and Mick Jenkins but, having giving them a vote of confidence last week, Pope surprised everyone by resigning himself.
Jenkins said: "Derek's put his lifetime's work into that club and for it to finish like that is all very sad. This has come as a big shock and you can't help but feel responsible for what's gone on. It couldn't have come at a worse time with the league restructuring next season.
"There's going to be a revolving door in the next week or so with players going out and others coming in, but Liam and I are aware that we could be part of that."
Pope, a builder by trade, has been chairman of the amalgamated club for four of its five-year history, but his association with the old Havant Town stretches back a further 20 years.
His financial imput has been crucial in establishing Havant as one of the area's most go-ahead non-league clubs - most particularly in developing Westleigh Park into a Conference-graded ground.
But poor home performances this season have seen gates halve to around 300 and disgruntled supporters again vented their wrath at the final whistle on Saturday.
Secretary Trevor Brock described it as "a very sad day" and can only hope and pray that Pope has not severed his club ties completely. "Derek's a passionate man and I can't imagine him just walking away," he said. "He's been the driving force ever since Havant have been involved in semi-professionalism and for him to go would be like cutting off the club's right arm. People who care about a club that deeply are very few and far between."
With their injury crisis still biting, the Hawks made three new signings before Saturday's game - young Portsmouth defender Ryan Hughes, plus returning pair Jamie O'Rourke from Newport IoW and Gary Connolly on loan from Bashley.
It made little difference though as goals by County's Gary Shephard, Gareth Phillips and John Phillips left them without a home win since October 4.
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