There was never any chance of Glan throwing away this three goal lead as they set about Llandyrnog with real purpose hardly giving the home side a sniff of goal throughout the ninety minutes.
Richard Owen twice came close to giving the visitors the lead in the opening four minutes, heading narrowly wide from a Nigel Barry free kick in the second minute then firing in another effort that was equally close after an Emyr Rowlands cross had beaten the keeper and come back off a post.
On 9 minutes Richard Owen gave Glan the lead with a goal of pure quality, holding off his marker with real determination before striking the ball perfectly from the edge of the area to find the corner of the net.
It was Richard Owen again involved on 17 minutes as he saw his shot blocked and partly cleared only for Emyr Rowlands to quickly return the ball into the middle for Nigel Barry to run in and score.
Two minutes later and Glan were three goals ahead as Richard Owen took advantage of a punch-drunk Llandyrnog defence to virtually walk the ball into an empty goal.
Things got worse for the Denbighshire side on 35 minutes as midfielder Miles Todd was dismissed for a second caution.
The second half saw Glan equally in control with Richard Owen going close to his hat-trick on 56 minutes and four minutes later a cross from Simon Kay was headed against the foot of a post by Kevin Roberts. Roberts again went close on 67 minutes, firing over following a good pass from Darren Jones.
Dave Ball had been virtually a spectator throughout but a long ball deep into the Glantraeth penalty area in the 92nd minute took an unkind bounce off the uneven playing surface to force a fine save from the Glan keeper and ensure an important clean sheet for the visitors.
Llandyrnog could not be faulted for lack of effort throughout but this was a day when Glan looked like they really meant business. Everywhere you looked there was a good performance in the Glan side, with the defence always in command and Richard F Owen linking up well with Nigel Barry to dominate the middle of the park.
Glantraeth: Dave Ball, Emyr Rowlands, Darren Jones, Warren Gibbs (Martin Bohana 80), Gareth Owen, Nigel Barry, Richard F Owen, Simon Kay, Richard Owen (Osian Pritchard 70), Kevin Roberts (Adrian Jurkowski 70) , Paul Rowlands.