Ireland's Daniel Holland dropped four strokes in the closing three holes at Ashburnham in West Wales last night to slump from second to joint 14th in the Welsh Amateur stroke-play championship.
The Castle man appeared to be heading for the runners-up spot behind the clear leader, Jimmy Mullen, with three holes to play.
But failure to make the green at the short 16th cost him a stroke and he followed that up by finding all sorts of trouble at the 17th, on which he took a double-bogey six and then he dropped another stroke at the last.
In the end, Holland's last round was a five-over-par 77 for a 72-hole aggregate of 285 - three-under par.
Castle clubmate, Alex Gleeson, was allowed to leapfrog him into a share of fourth place with an aggregate of 283, thanks to rounds of 68,72,71 and 72.
Gleeson finished with two bogeys. Mullen, from Royal North Devon, produced some spectacular golf to post a total of 273 - 15-under par. He won by nine strokes from Ben Westgate and Ashley Chesters.
Warrenpoint's Colm Campbell was joint 16th on 286, with Tarnan McLarnon and Dermot McElroy a further two strokes back in joint 22nd. William Hanna of Kilkeel was tied for 33rd on 201. Jonathan Yates of Naas missed the halfway cut.