Portishead Town paid the price after two missed penalties allowed Almondsbury to come from behind and steal the win.
After a frustrating defeat at Hengrove last Tuesday, Posset looked to make amends and went close after seven minutes when a free-kick on the edge of the box forced Stuart Wood into a good low save.
The Almonds responded well when a lobbed effort from Greg Parr beat George Shanks-Boon in the Posset goal but the hosts were able to clear off the line.
After the visitors dragged another shot wide, Portishead went close with a chance of their own, only for the Almonds defence to stand firm and block their shot.
On 32 minutes, Posset won a penalty after Rob Sivers was brought down in the box by Wood. Sivers stepped up to take the spot-kick himself but Wood redeemed himself by saving down low.
The visitors had the last chance of the first half with a half-volley forcing Shanks-Boon into a good save down low down to his right.
Posset started the second half well and opened the scoring on 47 minutes as a cross to the near post from Louie Elliot found the head of Nathan Trueman, who rose highest, to power home.
Soon after, Jack Sell cut in from the right and fired a low shot towards goal and forced Wood into another good save.
And moments later Elliot’s direct dribble into the box won Posset another penalty as he was brought down for the second spot-kick of the afternoon. Unfortunately for the home side the outcome was the same as Elliot saw Woods produce another good save down low to his left.
Just two minutes later, Sell skipped past the full-back and Wood and cut the ball back for Sivers to see his shot cleared off the line by Lewis Harvey.
Posset were left to rue missing their chances when Almondsbury levelled on 61 minutes through captain Ashley Knight, who ran on to a through ball and slotted past Shanks-Boon.
And the away side scored the decider on 81 minutes when Davies squared to Stuart Alexander who was able to tap home and complete the comeback.
Portishead will look to bounce back at Radstock Town in the league this Saturday.
The man of the match award sponsored by Jones Building Group was shared between Hamish Hurst and Ethan Hardy.
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