Despite a brace of goals from Sean Boyd, Finn Harps' automatic Premier Division survival slipped out of their own hands as they finished with 10 men, and had manager Ollie Horgan sent to the stand, at Richmond Park.
The result guarantees FAI Cup finalists St Pat’s second place in the Premier Division table, their highest finish since winning the title in 2013.
Without a win now in seven games, Harps will drop into the promotion/relegation play-off place if Waterford win at Longford Town on Saturday night.
As in their recent two games, St Pat's rang the changes with now fewer than six from their 3-0 defeat to Sligo Rovers last week, including a league debut for 18-year-old goalkeeper Josh Keeley.
After a slow start the game exploded to life midway through the half with four goals inside eight minutes.
Though Harps, with a good shape to them, started positively, they then played themselves into trouble inside 10 minutes, fortunate to get away without conceding.
Dan Hawkins’ poor ball put his skipper Dave Webster in trouble allowing Matty Smith to nod the ball in behind. Kosovar Sadiki got back well to make a vital block to Smith’s shot.
And while Robbie Benson and Darragh Burns had half chances, further negligent defending gifted St Pat’s the lead five minutes later.
Jamie Lennon’s superb long ball found Burns in space on the right and his low cross easily picked out the untracked run of Billy King who slotted home from close range.
Sloppy defending at the other end allowed Harps to level within two minutes.
Having been tripped by Benson, Boyd got up to drive his free kick through a brittle St Pat’s wall to the net leaving Keeley rooted to the spot.
In a manic period, Harps then snatched the lead with a fine goal on 20 minutes.
Barry McNamee took Ethan Boyle’s throw to dink a delightful ball into the area for Boyd to find the net with a glancing header.
Harps’ delight in having so quickly flipped the game around turned to fury two minutes later, though, as they conceded an equaliser.
They certainly appeared to have a case as Burns looked offside as he ran in behind onto another fine ball from Lennon to head past Mark McGinley with the Harps bench incensed at the lack of an assistant's flag.
Harps introduced Adam Foley at half-time and the winger might have put them back in front within two minutes.
Alert to a loose pass by Alfie Lewis, Foley skipped behind Shame Griffin only to slice his shot wide with only Keeley to beat.
Harps’ replacement goalkeeper Ger Doherty had to be at his best at the back at the other end to push Sam Bone’s low drive round post.
In end-to-end action, Saints striker King then had to clear off the line from Boyle following Hawkins’ corner.
Harps then lost their discipline late on with Sadiki receiving a second yellow card and dismissed for stupidly kicking the ball against Burns as he sat on the ground after fouling him.
St Pat’s might then have won it on 83 minutes, substitute Chris Forrester’s shot headed off the line by Will Seymore.
Harps manager Horgan, booked after St Pat’s second goal, was sent to the stand in stoppage time for dissent, with St Pat’s head coach Stephen O’Donnell also booked.
St Patrick’s Athletic: Josh Keeley; Sam Bone, Lee Desmond, Shane Griffin (Kyrian Nwoko 84), Jay McClelland; Alfie Lewis, Jamie Lennon (Chris Forrester 74); Darragh Burns, Robbie Benson, Matty Smith; Billy King.
Finn Harps: Mark McGinley (Ger Doherty 43); Ethan Boyle, Dave Webster, Kosovar Sadiki, Jordan Mustoe; Mark Coyle, Will Seymore; Karl O’Sullivan (Adam Foley h-t), Barry McNamee, Dan Hawkins (Johnny Dunleavy 77); Sean Boyd (Tunde Owalabi 90+3),
Referee: Neil Doyle (Dublin).
