Trailing when Levi Ives opened the scoring with a sensational long-range blast eight minutes into the extra-time, Kris Lindsay’s charges rallied and were rewarded for their endeavours when Johnny Lafferty scrambled home an equaliser late in the day.
That ensured that spot-kicks would be required to separate the sides and, after Joe Gormley missed the target from 12 yards, the visitors took full control before claiming a 3-2 victory that was arguably more comfortable than the scoreline suggests.
The first-half was a dour affair, although things might have been different had Lafferty been able to make a telling connection with the tantalising cross Mark Patton whipped in after just 18 seconds of play.
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Donnelly brothers Jay and Rory tested their luck for the hosts before Reds keeper Brian Neeson stood up to deny Lafferty after the former Ballinamallard United ace had sprung the offside trap to steal in on goal.
An injury to linesman Stephen Donaldson provided a rare talking point during a dull contest but, just after fourth official Christopher Morrison had taken up the flag in his stead, Neeson showed smart reactions to ensure that defender Garry Breen wouldn’t send Alan Teggart’s delivery into his own net.
There was a prevailing sense that whichever team showed greater urgency would get their rewards after the break and, though it was Cliftonville who seized the initiative, they found visiting keeper Niall Morgan in typically reliable form, with both Chris Curran and Joe Gormley frustrated to see good chances repelled by the Swifts custodian.
It was at the other end, however, where the game’s golden opportunity was carved out when Paul McElroy sent Patton scampering into acres of space but Neeson won this particular battle of nerves by standing up well to make the save.
After Dungannon skipper Chris Hegarty had blocked a Jay Donnelly drive on the line, Ives was perfectly placed to hoof a fizzing Patton strike away from danger ahead of Neeson producing the acrobatics to keep Lafferty at bay.
Morgan’s 84th minute save from Rory Donnelly was what ultimately sent the match to extra-time – however the Reds were adamant that their striker’s header had crossed the line before the keeper intervened.
Those frustrations soon subsided when, eight minutes after play had resumed, Ives broke the deadlock with an unstoppable dart of a strike that looked to have finally shattered Dungannon’s stern resistance.
The visitors failed to muster anything of real note thereafter but, crucially, neither did Cliftonville and it was the home side’s failure to go for the jugular that kept the Swifts in the tie – a situation they were only too happy to exploit when Lafferty bundled the ball past Neeson to set up a penalty shoot-out.
Gormley’s shocking miss allowed Dungannon to make a 2-0 lead through Paul McElroy and Chris Hegarty and, after Morgan had saved from Stephen Garrett, Jay Donnelly became the first Reds player to find the net from the spot.
Jarlath O’Rourke immediately restored the Swifts’ two-goal advantage, providing Alan Teggart with the opportunity to win it – only for Neeson to make a fine save.
Ives made no mistake with his kick to make it 3-2, meaning Ryan Catney simply had to score to keep Cliftonville in the competition, but he blazed over the top to send his side crashing out and nudge Dungannon through to a home contest with either Portadown or Linfield in next month’s semi-finals.
CLIFTONVILLE: Neeson, McGovern, Ives, Breen, C Curran, R Donnelly, McDonald, Bagnall, Catney, Gormley, J Donnelly. Subs: Garrett (Curran, 71 mins), McConnell (McDonald, 101 mins), Lavery, Maguire (R Donnelly, 110 mins), McMenamin, A Donnelly, Casey.
DUNGANNON: Morgan, Hegarty, Wilson, Armstrong, Clucas, McMullan, McElroy, Teggart, Patton, Lowe, Lafferty. Subs: Coney, Dykes (Armstrong, 106 mins), O’Rourke (Wilson, 101 mins), Burke (Patton, 86 mins), Hutchinson (McMullan, 78 mins), Campbell, Smyth.
REFEREE: Andrew Davey (Bangor)