Hull have been promoted to the top flight for just the second time in their 109-year history on a dramatic afternoon in which they were forced to wait 20 minutes before their fate was determined.
Steve Bruce's men were unable to secure the three points which would have guaranteed them second spot, yet they had a helping hand from Yorkshire rivals Leeds who beat third-placed Watford 2-1.
With just minutes to go in the Tigers' game, they were heading up against the 10-man Bluebirds yet an incredible finale with one red card, two penalties and a mini pitch-invasion left the door open for Gianfranco Zola's men.
However, with their clash delayed due to an injury, they were unable to score the goal which would have sent them into the top flight and it was Brian McDermott's side instead who got the goal to send the Tigers into delirium.
Former Hull loanee Fraizer Campbell had threatened to derail the Tigers' hopes by breaking the deadlock just after half-time, but two goals in five minutes through Nick Proschwitz and Paul McShane looked to have turned Hull's entire season back around.
Andrew Taylor was then sent off before Proschwitz had a penalty which would surely have guaranteed promotion saved. His spot-kick was kept out by David Marshall and it was Nicky Maynard who earned Cardiff a share of the spoils although matters at Vicarage Road would ultimately transpire in Hull's favour.
The hosts had the ball in the net early on as the ball ricocheted off George Boyd and crept in, yet the flag was up for offside long before.
When Boyd caught the defence napping Brady squandered a great chance to give Hull the lead when he curled his effort over.
Proschwitz was introduced at half-time and, during the interval, Hull would no doubt have been informed of Watford's leveller.
They were still heading up at that point, but the story's potential villain arrived at the start of the second half to throw a spanner in the works as Campbell broke the deadlock four minutes after the restart.
The striker drifted between the two centre-backs to collect a long ball and, with just one touch, coolly rolled the ball beyond Stockdale and into the corner.
However, nine minutes later, parity was restored. Quinn's ball came into Proschwitz and he managed to just stay onside and steer the ball into the far corner.
And there was better to come for the hosts, too. From a corner McShane got the wrong side of his marker and diverted Brady's inswinging delivery from the right into the bottom corner.
Few could have predicted what happened next. First Taylor was given his marching orders in the 90th minute for a foul on Ahmed Elmohamady then Hull had a stoppage-time penalty when Ben Turner crashed into David Meyler.
That prompted dozens of home supporters to spill on to the pitch and the delay clearly disrupted Proschwitz, who saw his spot-kick saved by Marshall.
And, just seconds later, Cardiff had a penalty of their own when the ball struck Abdoulaye Faye's hand. Maynard drilled the set-piece home to ensure Hull were left needing a favour at Watford.
And they got just that from Leeds as Bruce's men celebrated ending a three-year exile from the Barclays Premier League in incredible circumstances.