HOLDERS Boca Seniors crashed out of the Torridge Cup after a remarkable fightback from Halwill.
Andrew Wonnacott sealed a 4-3 win in extra time – after the Fresha Devon and Exeter League side trailed 3-0 with ten minutes to go.
Mark Gilfillan gave Boca the lead and Bideford defender Aaron Harper-Penman stepped off the bench to score twice.
But Harper-Penman blew the chance to complete his hat-trick and put them 4-0 up, blasting a late penalty over the crossbar.
From the resulting goal kick, Johnny Knight broke clear to pull one back and set the visitors' nerves jangling.
Jason Winser added Halwill's second with a penalty and Knight broke free again to hit the equaliser in stoppage time.
Wonnacott then scored a solo goal in the first half of extra time, completing the turnaround and giving Halwill a place in the quarter-finals.
Since taking over from long-serving manager Andrew Winser at the start of the season, Rob Holland has enjoyed being in charge.
He said: "That's the strongest side we have played this season so far but we are a good side ourselves.
"With the determination and spirit we have always had at Halwill, we are a match for anyone. All the lads put in a tremendous effort."
Halwill are fifth in the Devon and Exeter League second division and can go third by winning their games in hand.
Darren Todd, the Boca manager, slammed his players for a "woeful" performance.
"I have never seen anything like it in all the years of running that football team," he said.
"If we don't seriously change, we'll end up winning nothing this year.
"They were well in it, and fair play to them. They should have been 3-1 up at half time, they missed some glorious chances."
Boca do not play again until the trip to Bideford on February 2 in what will be just their tenth league fixture.