This was meant to be a grudge match - an edgy rivalry between Stephen O’Donnell’s current club and his old one.
Instead it was a four-gone conclusion by the hour mark.
Dundalk were clinical with their finishing, flexible with their approach play, and to be blunt, just more determined than their visitors.
Accordingly, five goals and three points went their way.
And they deserved it, setting the tone with such a bright opening, when Pat Hoban and Louie Annesley put them two up inside 15 minutes.
And then when St Pat’s threatened to come back into it just after the break, the Lilywhites reacted to their visitors best spell of the game by scoring twice on 53 and 54 minutes.
And that was that.
Key to all their good work was centre forward, Hoban, whose link play was impressive, as too was the positional discipline of their wide players, Daniel Kelly and Rayhaan Tulloch, thereby making it harder for Pat’s to maintain a narrow, defensive shape.
Even so they still should have reacted quicker to Hoban’s fifth-minute run which took him away from his marker before the Duns captain guided his header beyond David Odumosu.
If the Pat’s defending was poor for that goal, it wasn’t much better for the second, this one also stemming from a set-piece which Pat’s initially cleared before Tulloch retrieved possession to deliver a cross from the left.
Annesley reached quickest to it, steering his shot home from six yards.
And with that, Dundalk had a two-goal lead which might have been three had Joe Redmond not been brave enough to deflect Kelly’s shot wide.
We did catch glimpses of good play from St Pat’s, Mark Doyle placing one header wide, while the best move of the first half was theirs, Jamie Lennon providing a stunning pass down the left touchline which in turn was crossed into the penalty area by Chris Forrester.
But Darragh Leahy saved a certain goal with a brave clearance.
At the other end Tulloch’s run drew a fine save from David Odumosu but by now the play was switching from end to end, Jake Mulraney’s free-kick from an unfavourable angle striking the post, preceding follow-up shots from Lennon and Redmond.
Dundalk survived.
And come the second half they thrived, surviving an initial onslaught just after the restart before they grabbed two goals in a minute, Tulloch with the first from close range, after Odumosu parried Muller’s shot.
That was undoubtedly the game’s key moment for until that strike, Pat’s had dominated the early moments of the second half, pushing their full backs further forward in a clear attempt to find a way back into the game.
The tactics were working.
Their passing was slicker, their movement sharper.
And while chances didn’t come on the back of their pressure, they were still looking good, just like they did in long stretches against Derry on the opening night of the season.
But Tulloch’s goal killed that momentum.
And then came the best goal of the night, Greg Sloggett with the precise pass, Kelly with the finish.
The fifth came from Conor Malley, another tidy finish.
And by now O’Donnell was emptying his bench, thinking ahead to Monday. A standing ovation from the Dundalk faithful was granted to O'Donnell at the end. He earned it.
