Karl Sheppard’s brace propelled Cork City six points clear at the top of the table.
The 26-year-old broke the deadlock in the 22nd minute after the visitors were badly exposed on the counter attack, and Stephen Kenny’s men were left with a mountain to climb when Sheppard took advantage of more indecision in the Lilywhites back four to catch Dane Massey on the hop before rounding Gary Rogers to roll the ball home.
Dundalk were far from at their best and it looked like they were going to go down without a fight until substitute David McMillan dragged them back into the game with a classy 78th-minute finish.
That set up a tense finish but Cork City never looked like relinquishing their lead and Ciaran Kilduff was given his marching orders for a second bookable offence with five minutes to play, putting the cap on another miserable day on Leeside for the champions.
Substitute Josh O’Hanlon scored with his first touch to prove St Patrick’s Athletic’s saviour with a dramatic winner against 10-man Shamrock Rovers just seconds after his introduction at Richmond Park.
Striker O’Hanlon's first goal for the club brought a first victory of the season for Liam Buckley’s side to lift them off the foot of the SSE Airtircity League Premier Division table.
A riveting Dublin derby saw Rovers take a deserved early lead through Gary Shaw.
But the game turned with the sending off of Rovers’ Sean Heaney just past the half hour mark.
St Pat’s dominated thereafter with Kurtis Byrne equalising just before the hour before fellow substitute O’Hanlon won it with a thumping header.
Dan Byrne’s 75th-minute headed goal was the difference between the teams as Bohemians extended their unbeaten run to four games at the expense of Drogheda.
Bohs gave an early indication of their intentions when Paddy Kavanagh’s stinging drive was beaten away by Drogs keeper Stephen McGuinness inside three minutes.
But the remainder of the first quarter was a dour affair, with neither side offering any real threat as the respective defences dealt comfortably with any attacking moves.
Limerick recorded their second win of the season with a 1-0 win in Bray thanks to a Paul O’Conor wonder-strike.
The seasoned midfielder’s 25-yard hit was the difference in a game that lacked any real quality throughout.
Finn Harps claimed bragging rights in the north west as Ciaran O'Connor's 94th-minute winner saw the Donegal men beat Sligo Rovers 2-1 at Finn Park.
Raffaele Cretaro had given the Bit O'Red the lead on 59 minutes before Kilian Cantwell struck for his first goal for Harps nine minutes later.
Referee Arnold Hunter was at the centre of the late controversy as he adjudged Tobi Adebayo-Rowling to have fouled O'Connor inside the area.
O'Connor saw his penalty pushed away by Rovers goalkeeper Micheál Schlingermann, but the Dundalk loanee was alert to pounce on the rebound to record a big win for Harps who now move four points ahead of their neighbours.
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