It's not a contradiction in terms to label this as an error-ridden epic, one part Galway v Kerry 2008 with the torrential rain aspect, the other part Donegal v Kildare in 2011 for sheer longevity and twists and turns.
At the finish, Monaghan cast off that ugly statistic of 84 years without a Championship win at Croke Park, booking themselves a Saturday night blind date with the Dubs.
They have the kind of character that often ends up on the steps of the Hogan Stand on the third Sunday of September, but the panel is creaking badly. Already down Owen Lennon in midfield this season, Dick Clerkin could also be gone with some bruising on a leg bone.
Monaghan had to do things the hard way. In a monsoon they gifted Kildare two first-half goals from Emmet Bolton, but dipped into a well of resolve to dig themselves out, inch by inch.
Even at the very end of normal time Eoghan O'Flaherty looked to have edged Kildare into the quarter-finals with an injury-time point, but a final attack yielded a converted free in front of the sticks for Conor McManus.
Christopher McGuinness' coolly-taken goal in extra-time was enough to guide them home.
Glowing in victory, Monaghan manager Malachy O'Rourke said afterwards: "There were different times we could have thrown in the towel. We weren't playing particularly well at times and Kildare had momentum, but that's one thing the boys didn't do.
"They just kept working and playing for each other, playing as a team and as the game went into extra time we got stronger.
"We said as a group from the start of the year we didn't want to win an Ulster final and then drift off into the back roads again.
"There's great ambition in the group and we wanted to make sure we kept on an upward curve."
In the lead-in to the game, Kildare manager Jason Ryan had indulged in some mischief by suggesting that Monaghan captain McManus was the best free-winner in the country, something that slightly irked O'Rourke.
"I suppose we were just disappointed that he chose a public forum to do that. Saying something like that could possibly influence a referee and it works against him."
On Saturday they will be one half of the hottest bill in town, facing down All-Ireland champions elect, Dublin. It was noticeable how Monaghan played a very high line of pressure here, but the suspicion is that they might pull a few bodies back and give the Dubs a taste of a blanket defence.
"There is no doubting that they have very few weaknesses all over the field," cautioned O'Rourke.
"If you give them time and space they will run straight through you. We are delighted to be there."
He finished: "Even though we have only a week to recover, hopefully it will stand to us. That's where we want to be. There's no point crying about the opposition now. We just have to face up to it."
MONAGHAN: R Beggan; C Boyle, D Wylie (0-1), C Walshe; D Mone, V Corey (1-0), F Kelly (0-1); D Clerkin, D Hughes (0-1); P McKenna, C McGuinness (1-3), P Finlay (0-4, 4f); T Kerr, K Hughes, C McManus (0-5, 5f). Subs: S Gollogly for Clerkin, G Doogan for Kerr (both half time), K O'Donnell for McKenna (56m), R Wylie for Boyle (65m), J McCarron for Doogan (70m), P Donaghy for McCarron, K Duffy for O'Connell (start of extra time), McCarron (0-1) for Finlay (77 m)
Yellow cards: McKenna (48m), K Hughes (49m)
Black cards: Mone (90m, replaced by Doogan)
KILDARE: M Donnellan; C Fitzpatrick, H McGrillen, K Cribbin; P Lyons, F Conway, E Bolton (2-1); T Moolick, H Lynch (0-1); C McNally, P O'Neill (0-1), E Callaghan (0-1); A Smith (0-3), P Brophy, E O'Flaherty (0-4, 1f). Subs: E Doyle for Bolton (38m, black card), G White for Lynch (40 m), N Kelly (0-1) for White (50m), T O'Connor for McNally (53m), S Hurley for Lynch (60m), P Brophy for Hurley (66m), P Fogarty (0-2, 1 f, 1 x45) for O'Connor (77m), M Conway for O'Flaherty (85m)
Yellow cards: Lyons (29m), Conway (49m)
Black cards: Bolton (37m)
Referee: David Coldrick (Meath)