Havant paid a hefty price for some late errors as they went down 27-26 to strugglers North Walsham in the London & south east division at Hooks Lane.
Frustrated coach Simon Burns prowled the touchline as he watched his team throw the game away in the closing stages.
Poor decision making and flimsy tackling allowed the visitors to get their noses in front late on.
When Havant had the chance to snatch the win at the death, with a penalty, Burns was left fuming as his side took the wrong option.
Instead of taking the kick at goal, scrum-half Grant Morris tried a quick tap penalty and lost possession in the Walsham twenty-two.
Admittedly, Havant's goalkicking had been dreadful all afternoon but it was still too good an opportunity to pass up.
Burns said: 'It was a game we should have won but we did not perform to our standards.
'We had the greater amount of possession but when they had the ball we missed first-up tackles.
'It doesn't matter who you play, if you don't put the tackles in you don't deserve to win.
'All the way through the game, apart from the few minutes at the start, we were always leading.
'Then, three or four minutes towards the end, we let them in for a converted try to lose the game.
'Some of our decisions were not up to our normal standards.
'Fair play to North Walsham, they came and battled for everything.
'They had a couple of wise old heads in their ranks who got into us at the breakdowns and we got forced into that forward battle.
'Out wide we proved we had the quicker set of backs but we failed to use them enough.'
Havant were given a wake-up call right from the start when they fell asleep close to their line, allowing the visitors to score unopposed at a quickly taken line-out.
But the home side bounced back, started to impose themselves and, by half-time, led 13-8 through a James McSeveny penalty and tries from Nick Whittle and Gavin Hart.
When winger Jarryd Robinson extended the lead to 18-8 early in the second half, it seemed as though Havant would go on and win comfortably.
Walsham, however, refused to roll over and it suddenly became a see-saw affair.
Grant Morris got over for a bonus-point try for Havant but Walsham punished poor defending with two scores.
David Keyte looked to have given the home side the breathing space they needed with a penalty to put them ahead, 26-20, with five minutes to play.
But the hosts then threw the points away with an abject finish.
'If we had kept our heads and made better decisions we would have won,' said Burns.
'The result makes it that little bit tougher for us, looking over our shoulders at the teams below us.
'The players' faces at the final whistle suggests to me they know what they have to do.
'They are strong enough to come back from this and it is not all doom and gloom.'
Havant: Keyte; Chandler, Knight, Hart, Robinson, McSeveny, Morris, Wheeler, Cruddas, Davenport, Neill, Whittle, Barfoot, Horn, Thompson. Replacements: Blackburn, Copeland, Stapleton.