Dundalk overcame injury, illness and the setback of conceding an early goal to keep their dream of retaining the FAI Cup alive against Finn Harps at Oriel Park.
Having lost four players to Covid-19 and another to the flu since squandering a 3-1 lead with six minutes remaining in Ballybofey on Friday night, Vinny Perth's side showed real heart to fight back and finish the job in extra time to book their place in an eighth semi-final in the last nine seasons.
The holders had to do things the hard way having fallen behind to a Sean Boyd goal after just six minutes but despite missing as many as 11 first-team players, they fought back bravely, with Sean Murray levelling matters before a Patrick Hoban penalty and a stunning free-kick from Michael Duffy in extra time ensured their hopes of retaining the Cup for the first time in their history remain intact.
With it the club's European qualification aspirations also remain alive, with this result a major confidence boost for a side also battling the threat of relegation in the league at present despite all their resources.
Ollie Horgan’s visitors got off to a dream start when they took the lead after just six minutes.
An angled pass from Ryan Rainey saw Boyd steal in behind Darragh Leahy, with the striker killing the ball with a superb touch before drilling past Peter Cherrie.
Boyd would test Cherrie with a free eight minutes later but the Donegal side never really pushed on from that point to test a Dundalk outfit who had teenager Mayowa Animasahun and regular left-back Leahy at centre-back.
This allowed the home side to grow into the game and they threatened for the first time in the 18th minute when Cameron Dummigan’s pass picked out Sami Ben Amar, but the Moroccan could only fire to the right and wide.
Cherrie then did well to get down to his left to save a long-range effort from Barry McNamee on 22 minutes before Patrick Hoban headed tamely wide from a Murray corner a minute later.
Tunde Owolabi did fire over after capitalising on a mistake by Animasahun but that proved to be their last chance of note in the half as Dundalk drew level six minutes before the break.
A quick throw-in caught out the Finn Harps defence, with Hoban sending a bicycle kick across the six-yard box where Murray was on hand to finish at the near post.
Dundalk then had the first major chance of the half 11 minutes after the restart when Hoban’s ball released Duffy down the left but his effort was deflected wide by a combination of Shane McEleney and McNamee.
Harps captain Dave Webster then tested Cherrie with a snap shot from just outside the box after a corner broke to him on the hour mark, but the goalkeeper was equal to it.
The Scot then made a superb double save on 64 minutes to save firstly from McEleney and then Owolabi from McNamee’s corner.
There was no further openings for either side after that as extra time was called for and it was at this point that Dundalk came to the fore.
Hoban stung the palms of Gerard Doherty shortly after the restart before heading agonisingly over from close range after a teasing cross from the right by Murray.
The striker would make it third time lucky from the spot on 97 minutes when he blasted to the righthand corner after Ben Amar was adjudged to have been fouled in the box by Webster.
Substitute Ryan Connolly attempted to respond from a free-kick five minutes later but fired well over.
The result was then put firmly beyond doubt on the stroke of half-time when Duffy curled a stunning free-kick over the wall and past Doherty to the top lefthand corner.
Finn Harps threw caution to the wind in the second half in an attempt to get back into the game but unlike on Friday night in Ballybofey, their opponents stood firm.
The holders are into the last four and with players to return before the semi-finals at the end of October, they can’t be written off just yet.
Dundalk: Peter Cherrie, Raivis Jurkovskis, Mayowa Animasahun, Darragh Leahy, Cameron Dummigan; Greg Sloggett, Will Patching; Sami Ben Amar (Mark Hanratty 101), Sean Murray (Enda Douglas 115), Michael Duffy; Patrick Hoban (Ebuka Kwelele 121).
Finn Harps: Gerard Doherty; Ethan Boyle, Shane McEleney, Kosovar Sadiki, Dave Webster (Stephen Doherty 105+2); Mark Coyle; Karl O’Sullivan, Barry McNamee (Dan Hawkins 105+2), Ryan Rainey (Ryan Connolly 88); Tunde Owolabi (Luke Rudden 113), Sean Boyd (Adam Foley 71).
Referee: Ben Connolly (Dublin).