Kircassock Vic sprang a 25/1 shock in the hunters chase at Downpatrick to give Graham Watters his first success under rules.
The James Lambe-trained gelding crept into contention two from home only to make an error.
He stayed on gamely on the run-in, however, to grab even-money favourite Bally Wall close home for a neck success.
Lambe was full of praise for the 18-year-old amateur who hails from County Meath.
"Graham gave him a fantastic ride and it's his first winner on the track," said Lambe.
"He had a little issue with breaking blood vessels and I didn't think he would handle the ground today.
"He could go to Down Royal on Boxing Day. On a going day he's a decent horse."
