Damien Mooney eagled the par-four fifth on his way to a three-shot victory over former Ryder Cup player Philip Walton in the Dr William Flynn Memorial Trophy on Friday.
Mooney holed out from 97 yards in a blistering burst of scoring that saw him reach the turn in six under 32 at Shannon Golf Club in Co. Clare.
The Belfast golfer failed to maintain that momentum after the turn, with a trio of bogeys at the 14th, 15th and 16th slowing his charge.
However, his tally of seven birdies, an eagle and four bogeys gave him a three-shot win over Walton, who signed for a two-under par 70.
Limerick's Tim Rice and his amateur partners won the team prize with 90 points.
Dr William Flynn Memorial Trophy, Sponsored by TaylorMade, Shannon Golf Club (Par 72)
67 Damian Mooney (Damian Mooney Golf)
70 Philip Walton
71 David Ryan (Cahir Park), Michael Mulryan (Cregboy Golf Academy)
72 Mark O'Mahony (Titleist National Fitting Centre), Tim Rice (Limerick GC).