James McAuley and Jimmy Gough celebrate McAuley's 14th winner at Dundalk this year© Photo Healy Racing
Dalvey dropped back in trip to winning effect in the extended 10 furlong handicap at Dundalk.
He was ridden a furlong and a half down by Jake Coen and ran on strongly to lead at the furlong pole.
He was kept up to his work as Grandmaster Flash finished off well. There was half a length between the 7/1 winner and 12/1 runner-up at the winning post. Zoom Tiger completed the placings a further two and a half lengths away at 25/1.
Trainer James McAuley said: “Derek O’Connor told us he was nearly there after running on the beach (at Laytown) and he’s never looked back since.
“We ran him over two miles because he was working slow but since then he’s been getting quicker and quicker. He’s starting to realise the potential that he had.
“That’s 20 winners for the year for us and 14 up here. We never have more than about 16 riding out so it’s been a brilliant year.”
Dalvey won over two miles in Dundalk last month.
Additional reporting by Alan Magee
