Horndean blew a three-point lead in the fifth set to lose 3-2 to Solent II in National League division two south at Highbury College.
The hosts appeared to be well on their way to a priceless victory after cruising to a 14-11 advantage in the decisive set.
But the title favourites launched a strong comeback to level the scores 14-14 before going on to break the Deans’ hearts with a 20-18 success.
The two sides were so evenly-matched, they had both racked up 108 points in the two hours and five minutes of gruelling action.
Horndean player-coach Nasser Ssemuwemba was left frustrated, though.
He said: ‘It was a very close game. Definitely, not one for the faint hearted.
‘It had everything, the passion, the desire, the fighting spirit and there were also some very good rallies.
‘Unfortunately for us we came short in the fifth set.
‘We gave our best but could not find that elusive point.
‘In closely-contested battles like this one, experience and concentration are key factors.
‘And I’m afraid to say we disappointingly lacked that in the final stages. It was a painful loss for us.’
The Deans took control of the opening set with big jump-serving duo Leandros Tsikras and Konstantinos Yiannakkos on the rampage.
The pair’s powerful serves inspired a 25-16 success before Solent upped their tempo in the second set to level with a 25-22 win.
The Deans then regained the lead 25-22 before the visitors pushed the match to a pulsating decider with a 25-18 success in the fourth.
Horndean trio Haakon Lie, who was named man of the match, Damian Roberts and Ssemuwemba looked lively and ruthless as they opened up an 8-6 lead.
They then needed just one point for the match at 14-11.
But a catalogue of individual mistakes opened the door for the visitors to launch their fightback.
The battle for a two-point lead swung from side to side before Solent’s defence and blocking finally earned them victory.
The Deans host Bristol at Highbury College on Saturday (11am).