There was late drama at the Brandywell as Dundalk held on for a magnificent three points defeating Derry City by two goals to one.
Derry started the game fairly comfortably and Dundalk were dealt a blow in the 9th minute when Liam Burns had to leave the field with what looked like a fairly serious leg injury. However, against the early run of play, a piece of shoddy defensive clearing saw the ball fall at the feet of the industrious Michael Rafter who slotted home from 12 yards to give the Lilywhites a shock lead.
The remainder of the half saw long spells of Derry possession and a few half chances but the home side seemed to lack any cutting edge in the final third. This was summed up in the 31st minute when Mark Farren was clean through but seemed in two minds about when to pull the trigger and was brilliantly challenged by the excellent Luke Danville.
Dundalk will have been buoyed at half time at how well they were dealing with Derry's threat but Declan Devine will have been furious at the lack of urgency his charges seemed to be showing.
The second half began once again with Derry having most of the possession, and in the 50th minute a Barry Molloy header was somehow clawed away by Peter Cherrie as Derry tried to claw back the deficit.
But in a moment Eddie McCallion and Gerard Doherty will wish to forget, they both left the ball to each other and Shane O'Neill nipped in for the easiest goal he is ever likely to score. At this stage it seemed a long way back for the Candystripes and Devine changed his system to a 3-4-3 in an attempt to get something out of the game.
The remainder of the half was played almost exclusively in Dundalk's half and they were superb to a man as they thwarted the waves of Derry attacks.
In the 84th minute Dermot McCaffrey sent over a corner and substitute Rhuadhri Higgins headed the ball past a despairing Peter Cherrie to set up a tense finish to the game.
But the main drama of the night wasn't far away and in the 90th minute David McDaid was clean through on goal and was cynically brought down by the Dundalk captain Chris Shields. Damien Hancock immediately pointed to the spot and sent off Shields for a professional foul.
McDaid placed the ball on the spot before chaos erupted as the linesman overruled the referee's decision and Hancock gave a free kick on the 18 yd line. After the free was taken and a super save by Cherrie, Derry were understandably fuming about the late call.
This is not to take away from a magnificent Dundalk performance and for their defending alone they will feel they deserved the points. Derry will however be disappointed given the amount of the ball they had and it is back to the drawing board before entertaining Shamrock Rovers in the Setanta semi-final on Monday.
Derry City: Gerard Doherty; Dermot McCaffrey, Eddie McCallion, Ryan McBride (Brian McGroary 64), Simon Madden (Ruaidhri Higgins 64); Stephen McLaughlin, Barry Molloy, Kevin Deery(c), Patrick McEleney, David McDaid; Mark Farren.
Subs not used: Eugene Ferry, Shane McEleney, Michael Barr, Barry McNamee, Matthew Crossan.
Yellow Cards: Ryan McBride (30), Kevin Deery (92).
Dundalk: Peter Cherrie; Liam Burns (Robert Waters 9), Luke Danville, Ben McLaughlin (Paul Walsh 68), Eoghan Osbourne; Chris Shields (c), John Mountney, Peter Thomas, Shane O'Neill (Chris Reilly 89); Michael Rafter, Gary Shanaghan.
Subs not used: Ger Hanley, Gareth Coughlan, Dan Cunningham, Michael Osobe.
Yellow Cards: Peter Thomas (23), John Mountney (61), Shane O'Neill (83).
Red Card: Chris Shields (90).
Referee: Damien Hancock.
Attendance: 1,500 (estimate)
extratime.ie Man of the Match: Luke Danville.