Dundalk bounced back from their Europa League defeat in Bratislava during the week by kicking off their defence of the FAI Cup with a 1-0 win over Cobh Ramblers at St Colman's Park.
Georgie Kelly, one of nine changes to the side that started in Slovakia on Wednesday, scored the winner with 23 minutes to go, the striker rising high to meet Sean Gannon's cross and bury his header past Paul Hunt.
The first division side pulled off a major shock when they beat the Lilywhites in the semi-finals of the EA Sports Cup last season and they started brightly here with Ian Turner firing at Aaron McCarey early on.
Dundalk almost hit the front in the 13th minute when Sean Hoare cracked the underside of the bar after Lido Lotefa flicked on a Patrick McEleney free. Referee Ray Matthews waved away Hoare's protests that the ball had crossed the line.
With the wind making life difficult, it was evenly matched after that but the hosts almost took a one-goal lead into the break with Dave Hurley's effort clipping McCarey's post before drifting wide.
Perth turned to his star-studded bench by introducing Sean Gannon and Michael Duffy and the changes paid dividends as Kelly hit the opener in the 67th minute.
Gannon was involved, collecting a pass from John Mountney on the right before whipping in a fantastic cross for the Kelly who made no mistake with a downward header.
Cobh pressed for an equaliser but the closest they came to forcing extra time was when Cian Leonard latched onto a long ball from the back but he couldn't keep his effort on target and Dundalk saw it out comfortably to book their place in round two.
Elsewhere in the FAI Cup, Crumlin United booked their place in the second round of the cup thanks to a 3-1 victory over Malahide United at the Pearse Park Astro.
Crumlin went behind early on but goals from Craig Walsh, Ger Brady and Alan McGreal before the break ensured their progress.
Meanwhile it took a penalty shoot-out to seperate St Michael's and Glengad United after the sides finished scoreless.
Glengad won 8-7 on penalties.
Cobh Ramblers: Paul Hunt; Kevin Taylor, Charlie Fleming, Ben O'Riordan, Greg Murray; Dave Hurley, Charlie Lyons, Ian Turner; Bryan Murphy, Stephen O'Leary; Cameron Harlson (Andrew Cronin 74).
Dundalk: Gary Rogers; James Carroll (Sean Gannon 51), Brian Gartland, Daniel Cleary, Cameron Dummigan; Sean Hoare, Patrick McEleney; John Mountney (Sean Murray 76), Lido Lotefa (Michael Duffy 58), Daniel Kelly; Georgie Kelly.
Referee: Ray Matthews.