One of the few elements we're starved of in top flight football is one of the most gripping in the divisions below. Those teams who fall just short of the automatic promotion spots get a final crack in the playoff format, where an entire season can boil down to just a few matches.
In the case of the Championship, 46 games come down to two semi finals and a final for four teams, and their dreams of reaching the Premier League can be dashed in the space of 180 minutes.
Third take on sixth and fourth take on fifth, both over two legs, with the prospect of a one-off Wembley showdown as the final hurdle in each competing side's quest to reach the promise land.
Last season, Derby, led by rookie boss Frank Lampard, secured their place in the playoffs on the final day of the regular season, while Leeds let their lead in the top two places slip towards the end of the campaign and had to settle with their own playoff berth.
Both sides found themselves in the same position - so to speak - but with entirely different mindsets heading into their fixtures. Leeds were dejected, Derby were elated.
It's key to remember the backdrop to this particular tie. In just the second game of the season, Leeds had wiped the floor with Derby on their patch to secure a 4-1 win, and then, 25 matchdays later, huge controversy struck when it was revealed that Marcelo Bielsa had sent spies to watch the Rams' training regimes. Thus, 'Spygate' was born.
Despite the moral and ethical sidenotes prior to their second league clash, Leeds once again put in a dominant display to leave worthy 2-0 winners. The whole incident sparked condescending chanting and heckling from the Leeds supporters in the direction of Lampard, which would only seek to serve as a cruel foreshadowing to an eventually crushing downfall.
So, first leg comes and goes - not without controversy of its own - but Leeds took control of the tie with a hard-fought 1-0 win at Pride Park.
The chanting continued.
Leeds, for all their late failings in the division, had one foot on the Wembley turf, all the while Derby's late flurry of their own looked like falling foul to the gulf in class between the two sides that the league table suggested.
Head back to Elland Road for the return leg and, backed by their immense home support, Bielsa's new-look Leeds side looked primed and ready to finish the job. Just 24 minutes in and it looked like curtains for Derby when Stuart Dallas prodded in from close range.
This, however, was no ordinary Derby side. Rejuvenated by Lampard's presence, backed by a raucous away following and boasting some exciting young players of their own, they weren't to be rolled over. That said, how important was their late leveller on the stroke of half time? Fairly colossal, you'd think.
Leeds had struck the crossbar to narrowly avoid extending their lead, while Derby too came within a whisker, only too to be denied by the upright. Yet a calamitous misunderstanding between Liam Cooper and goalkeeper Kiko Casilla at the back was their invite back into the tie, as Jack Marriott scored with his very first touch.
Game well and truly on.
Could Leeds regain a foothold in the match? Would that late gift of a goal revitalise Derby after the restart?
Mason Mount's strike less than a minute after half time gives you the answer to that. The young, energetic and hungry visiting side showed their best colours, ripping through a disorganised Leeds with frightening efficiency.
On the up at that point, another moment of madness presented the Rams with the chance to well and truly turn the game on its head, as Cooper needlessly tugged Mason Bennett in the box to gift the visitors a penalty. Harry Wilson was cool as a cucumber. 3-1 and 3-2 on aggregate.
In the manner those not too fond of Leeds often say, they were falling apart.
But this was a Leeds side who had been flirting with the automatic promotion places throughout the entire season. They were by no means pushovers, and an opportunity to return to the top tier for the first time in 15 years wasn't going to be relinquished quite so easily.
A match that truly had everything you could want ramped up the tension even further through Dallas' second of the night, a fine individual goal to strike back and level the tie on aggregate at 3-3 not four minutes later.
An atmosphere perfectly divided by fear and ferocity from both sets of supporters was in limbo. Equal on so many levels, it would require a disadvantage of sorts to aid in altering the outcome. Which is the unfortunate mantle that Gaetano Berardi took upon himself.
The hotheaded Swiss is known for his unfavourable disciplinary record, and the raw emotion of the occasion got to him once more where a second yellow card for a reckless challenge would hand him his tenth career sending off. At this point the ball was firmly in Derby's court, and their exuberant side grasped the opportunity with both hands.
Marriott netted his second of the night with five minutes remaining, a goal that finally broke the valiant Leeds resistance with a fabulous deft chip over the onrushing Casilla - remarkably assisted to him by marauding centre back Richard Keogh.
The scenes of jubilation in the away end and visiting dugout, coupled with despondent and anguished faces of the home supporters and players encompassed the overriding feelings at the time.
While there was still time left to play, it appeared as if the final, killer blow had been landed, and the underdogs were set to prevail. Leeds still piled forward in search of parity, with Scott Malone's late sending off not enough to disrupt the narrative.
'Stop crying Frank Lampard', over the course of roughly 45 minutes, had simmered away into mere disgruntlement and desolation. A rousing away end reached peak pandemonium. Contrasting sets of emotions were so unalike that they didn't belong in the same vicinity.
Derby were going to Wembley and Leeds were set to plug it out in the Championship once more, but not without playing their part in an all-time second tier classic.
People have claimed this match to be a perfect advert for Championship football. But scratch that. This was the perfect advertisement for football in general.
A captivating 90 minutes that adequately captured all the elements that make the sport such a wonderful spectacle. Unfortunately for Leeds, they once again ended up on the wrong side.