Linfield advanced to the League Cup final as Dungannon’s hold on the trophy was finally ended.
It took extra time for this semi-final at Stangmore Park to produce a goal.
And it was Andrew Waterworth who came up with the winner just two minutes after the game restarted, scoring from close range after a shot was saved.
The Swifts, who gave it a real go, must now turn their attention to the league, and dragging themselves away from the bottom.
Boss Kris Lindsay can take encouragement from his side’s battling performance. But ultimately Linfield produced the goods when it mattered. Dungannon made four changes from Saturday’s draw with Newry.
Among those brought in was goalkeeper Niall Morgan, because Alex Moore - on loan from Linfield - was not allowed to play. Skipper Ryan Harpur was also back, although the absence of Jake Dykes, David Armstrong and Douglas Wilson left them short of defensive cover.
For Linfield, it was the same team that started the weekend’s 4-1 demolition of Crusaders. The Blues enjoyed some early possession with Kirk Millar going close in the 14th minute.
He looked to go one way, before turning the other and sent a curling left-foot effort just past the far post.
Dungannon settled and had two chances in a minute.
Paul McElroy dragged a left-foot shot wide, then Alan Teggart cut inside from the wing and aimed straight at goalkeeper Roy Carroll.
In the 25th minute Patton’s cross sought out Teggart, who came running in at the back post but headed into the side netting.
Joel Cooper had a go for the visitors, cutting inside and aiming for goal, but the angle was tight and Morgan blocked. Dungannon came so close to snatching the lead 10 minutes from the break.
Big defender Chris Hegarty got on the end of Patton’s free-kick and, but his header clipped the post and spun wide. Linfield came close twice in a minute in the early stages of the second half.
First a free-kick was awarded around the corner of the box and Niall Quinn went for goal, but his effort was pushed wide by Morgan.
Moments later Mulgrew let fly with a stunning effort which hit the crossbar, bounced down, but crucially didn’t cross the line.
Jordan Stewart then sent a left-foot effort just wide as the Blues continued to push.
In the 65th minute Waterworth was inches from getting on the end of a Cooper cross, but arrived a fraction too late at the back post.
Waterworth then turned provider, with Morgan making a point-blank save to deny Stewart. Soon afterwards Cooper nicked possession in midfield, burst into the box, but was denied by a fine Hegarty challenge. Michael O’Connor was introduced as a sub by the visitors and almost made an instant impact, sending a low effort just wide.
With two minutes to go Josh Robinson tried his luck from distance, but again Morgan was up to the task.
It meant extra time, and it took just two minutes for the Blues to make their mark.
The ball was played to the back post and Millar’s shot was blocked by Morgan at close range, but Waterworth was there to slot home the rebound. Quinn came close to making it 2-0, but blazed over from a glorious position.
Dungannon pushed for an equaliser and a shot from young sub Oisin Smyth drew a good save from Carroll.
McElroy also sent a shot dangerously across the face of the visitors’ goal, but no-one could get a touch.
DUNGANNON: Morgan, Lowe, Hegarty, Clucas, O’Rourke, Harpur (Hutchinson, 71), McMullan (Smyth, 97), Patton, Teggart (Hughes, 94), McElroy, O’Carroll (Lafferty, 77). Subs not used: Addis, Burke, Campbell
LINFIELD: Carroll, Robinson, Callacher, Casement, Quinn, Mulgrew, Millar (Mitchell, 96), Fallon, Cooper (O’Connor, 81), Stewart, Waterworth
Subs not used: Deane, Forde, Clarke, Garrett, Reynolds
Referee: Steven Gregg (Ballyclare)