Sligo Rovers were beaten for just the second time at home this year as Dave McMillan's 14th goal of the season was enough for Dundalk to claim the points at the Showgrounds.
Dave Robertson's side were handicapped from early on as captain Craig Roddan was dismissed with just nine minutes played.
Rovers had welcomed back both Roddan and Raff Cretaro from respective suspensions following the FAI's ruling that both served their bans during last Saturday's abandoned match with Finn Harps. Roddan's return lasted less than ten minutes however as he was issued his marching orders following a challenge on Daryl Horgan in the middle of the pitch. Referee Paul McLaughlin showing little doubt in his decision as he promptly dismissed the Rovers skipper for the second time this term.
Things immediately went from bad to worse for the Bit O'Red as Dundalk took the lead just 90 seconds later. Ronan Finn split the Sligo defence with a through ball for Patrick McEleney who, finding space behind the Rovers back four, squared for the league's top scorer McMillan who was left with a simple close range tap-in.
Dundalk goalkeeper Gary Rogers, fresh from his involvement with the Irish squad in Belgrade squad just 24 hours previous, was involved soon after as he almost gifted Rovers a leveller. The former Sligo number one came to meet Daniel Kearns' long ball forward but instead of nodding it to safety, Rogers could only head the ball vertically into the air. Sligo's Kieran Sadlier assumed possession but was denied by a well marshalled Dundalk rearguard who managed to get back in time to clear the danger.
Horgan was a threat on the Lilywhites' left all evening and was unlucky to see his swerving effort from the edge of the box kiss the Rovers crossbar just past the half hour.
Horgan was involved again seven minutes from the break. The jinxing Sean Gannon finding Horgan at the front post, but the unmarked winger was unable to find the target on the turn. While McMillan couldn't apply the finishing touch to Horgan's superb searching cross soon after as the champions finished the half well on top.
The FAI Cup holders never looked far from grabbing a second and came close to doing so on 57. Horgan's initial set piece came back off the head of Cretaro while the former Cork man's second bite of the cherry fizzed perilously past Schlingermann's left hand post.
Substitute Robbie Benson almost found Dundalk's second ten minutes later when he latched on to John Mountney's free-kick from the right. Benson unable to repeat his Warsaw heroics as he saw his first time volley come within inches of the Sligo crossbar.
A man down, the home side displayed plenty of endeavour and industry.
Dundalk came within a lick of paint to securing the points with six minutes remaining. Horgan's cross evading the reach of Schlingermann before McMillan tapped the ball against the woodwork whilst under pressure from Leahy who eventually scrambled the ball away.
Rovers had a penalty shout turned down three minutes from time when Andy Boyle caught Gavin Peers inside the Dundalk box.
Sligo Rovers: Micheál Schlingermann; Tobi Adebayo-Rowling, Gavin Peers, Mick Leahy, Jimmy Keohane; Daniel Kearns, Craig Roddan, Kieran Sadlier (John Russell 68), Liam Martin; Raffaele Cretaro, Achille Campion (Mikey Place 86).
Dundalk: Gary Rogers; Sean Gannon, Andy Boyle, Brian Gartland, Dane Massey; John Mountney (Darren Meenan 70), Ronan Finn, Stephen O'Donnell; Daryl Horgan, Dave McMillan (Dean Shiels 89), Patrick McEleney (Robbie Benson 62).
Referee: Paul McLaughlin.