Mauricio Pochettino and Pep Guardiola were so overcome by the nerve-shredding tension of this night that their only answer was to start shedding clothes.
Tottenham boss Pochettino's trademark black coat was hurled amid the drama of Raheem Sterling's disallowed injury-time strike while Manchester City counterpart Guardiola emerged from the same melee minus his stylish grey cardigan.
It was like Etihad Stadium's version of rush hour - both technical areas populated by scores of people, the clock ticking down while VAR did its work.
It was a moment of glorious sporting carnage and matchless excitement that capped off a night that ranks alongside the most dramatic the Champions League has witnessed.
City and Spurs did not waste time warming up. Instead, it was chaos from the start. No sparring or cagey exchanges here - the first 21 minutes brought five goals and there was no let-up from first whistle to last.
It is rare you get a game that starts at such breakneck speed and simply keeps going until the 95th minute - or a bit longer if you add in VAR deliberations.
These two teams were magnificent in different ways and it was always going to be cruel on the loser, but neutrals could bask in the heady excitement of a game that delivered everything that makes this sport great.
And it was all presided over by the newcomer VAR, adding an extra dimension of delayed tension.
First, Fernando Llorente's ultimately decisive goal was awarded after lengthy consultation over a potential handball, while Sterling's late effort was ruled out with Sergio Aguero deemed just offside.
It was a night not to be forgotten, even for those of us who have seen so many things football has to offer.
Guardiola called on the City fans to show how much this competition - somewhat unloved by a section of them - meant to the club. There was even the questionable garnish of thousands of flags placed on seats to help things along.
Yet on this night, with all that was at stake and the drama that duly unfolded, a searing atmosphere inside the Etihad was a given. It may have ended in defeat for City but there is no need to question their fans' desire to win the Champions League.
As both teams traded blows in this absorbing contest, there was almost a danger of losing track.
Sterling levels the tie. Son Heung-min strikes twice to leave City needing three. Bernardo Silva and Sterling bag two of those before half-time. Into the second period and Aguero looks like he has done it as he puts City 4-2 ahead. Llorente changes the storyline by bundling in for 4-3. Sterling almost writes the late plot twist but VAR closes the book.
Compelling for every second.
The scenes at the final whistle told the tale. City's players hit the turf in despair after running the full gamut of emotions, while Spurs, Pochettino and everyone in their camp raced towards their supporters in the far corner of the Etihad.
They had experienced myriad emotions in this one remarkable game - this Champions League hothouse - and emerged victorious at the other side.
City must come again when these two meet here again on Saturday lunchtime, their target of a historic quadruple reduced now to a domestic Treble, with the Premier League the priority.
As for Spurs, how many cynics had to scratch out the tired insult "Spursy" - code for "if they can mess it up, they will" - after Sterling's goal threatened anguish before VAR intervened?
This was a wondrous sporting occasion and what a feather in the cap of Pochettino, whose side dredged every possible reserve and mined all their qualities to set up a semi-final against a dangerous young Ajax side.
Pochettino's reputation has soared in this Champions League campaign and, if fortune favours the brave, the Argentine earned it with his refusal to play safe and simply defend that 1-0 lead from the first leg.
He was shorn of midfield options with Harry Winks and Eric Dier injured, yet showed tactical courage by sending on Llorente when influential midfielder Moussa Sissoko went off injured with City 3-2 ahead on the night but with Spurs set to progress on away goals if they could keep City from scoring again.
Llorente went on, Dele Alli dropped deeper and Pochettino's reward for his bravery came with that bundled, scrappy goal from the Spaniard 17 minutes from time.
As for Son, he added to his reputation with an another influential display, the South Korean again filling the breach in the absence of injured England captain Harry Kane.
Son is a player of the highest class, with pace, talent, movement and great intelligence that troubled City all night.
He may have been the beneficiary of sloppy defending from Aymeric Laporte and questionable goalkeeping from Ederson for his first goal, but the second was a sweeping, curling strike right from the top drawer.
It is stretching credibility to suggest it settled Spurs' nerves, but it gave them equilibrium and something to protect after Sterling's early goal.
In the wider context, Spurs will now feel they have a real chance of making their first Champions League final, even though they must get past Ajax, the young team that have all of Europe talking.
And what a night it will be in Tottenham's magnificent stadium - the occasion of chairman Daniel Levy's dreams when he imagined Spurs in their new home.
It may have come even quicker than he thought. Let's not forget Spurs were in danger of not even reaching the knockout phase after a home defeat by Barcelona, a miserable defeat at Inter Milan and a careless draw at PSV Eindhoven in the group stage.
What a tribute it is to Pochettino and his players that the prize of a place in the Champions League final in Madrid is just two games away.
What joy and satisfaction this achievement will bring them once the adrenaline surge of one of the great European ties cools and they can reflect on this momentous night.
City and Spurs did football and themselves huge credit, but it is Pochettino's men who go through after a contest that will remain indelibly stamped on the memory of all who saw it.