Connacht secure Champions Cup berth against shell-shocked and under pressure Munster
Connacht 35 Munster 14
The place literally rocked - to celebrate a night like this and, potentially, so much more to come. They even stole Munster's song - the Fields of Athenry - or, at last, regained it.
This was another testament to Connacht's wonderful self-belief, a paean to the gospel of Pat Lam, for whom freedom of expression means playing the game of rugby the way it is meant to be played.
Connacht stormed their way to a bonus point victory against a shell-shocked Munster side whose early two tries from Simon Zebo and Mike Sherry had given them a 14-6 lead after just 25 minutes.
However, true to their enterprising, never-say-die attitude, Connacht bounced back to lead 20-14 at the break with spectacular scores from Niki Adeolokun and a Penalty Try as ill-disciplined Munster were reduced to just 13 men at the break.
Further scores from Adeolokun and Finlay Bealham sealed a run-away victory and maintained the westerners quest for a home semi-final in the Pro12 play-offs, as well as absolutely confirming their Champions Cup qualification, for the first time on their own merits.
Now, it is Munster's European hopes which are threatening to unravel and it will be an extraordinarily nervy Irish Independent Park which will welcome their chasing rivals Edinburgh in a fortnight's time.
This defeat, even more than the harrowing loss in the Aviva, will fester from now until then as they languish outside the European qualification places.
Connacht had won two of the last three against their southern rivals but had never before done a seasonal double against the former two-time European winners; another record was being lined up by the most exciting team in Irish rugby.
For a decent stretch of the first-half, though, it didn't look as if their latest crack at history would materialise as Munster played some decent rugby, scored a spectacular try through Zebo and found Johnny Holland in fine form at half-time.
It was a damning indictment, though, that when the pressure was applied by their hosts, they couldn't withstand the elemental force, failing to score for more than an hour.
Munster were desperate for a result after blowing the chance of an easy penalty to secure a draw in the Aviva last time out and, after being widely criticised for hauling off out-half Johnny Holland in that game, Anthony Foley stuck with him to start this game, despite whispers of a hamstring injury that had curtailed his time on the training paddock.
Munster lost the toss but on receipt of possession from the opening restart used it well and immediately found territorial advantage and both Keith Earls and Simon Zebo making good ground but without really threatening the 22.
The first scrum saw James Cronin penalised and allowed the westerners to make their first visit to enemy ground, some good ball retention from the lineout forcing CJ Stander to cough up the first penalty chance of the game.
Shane O'Leary, the fourth-choice out-half, made a first-class connection from the penalty effort some 40 metres out and it was first blood to the westerners.
As if miffed at all the praise Connacht have been receiving for their enterprising rugby, the visitors replied with a score straight from the Pat Lam playbook in the 11th minute of a blistering opening stanza.
Holland's burst and wonderful pass out the back freed the gambolling Jack O'Donoghue and, although Simon Zebo still had work to do from 20 metres out but he evaded a host of would-be tacklers with a slaloming run and touchdown.
Holland converted for 7-3 and when his counterpart kicked dead moments later - O'Leary had earlier been charged down but Conor Murray was never in danger of scoring the try - these were testing moments for the home side.
However, from the resulting scrum, Stephen Archer was penalised this time and O'Leary made no mistake with his touch finder. Cronin was then harshly penalised on the floor when it seemed he had made a fair steal.
Ben Whitehouse thought differently however and O'Leary added the extra punishment on the board to narrow the deficit to 7-6 with nearly a quarter of a breathless quarter gone.
However, Munster had identified Connacht's unwillingness to kick from their 22 this term and, pressing up with a quick defensive line, forced Bundee Aki to knock on O'Leary's pass and give the men in red a perfect scrum platform virtually beneath the posts.
Munster tried a few rumbles but Connacht defended their line despite CJ Stander being held up twice, albeit then illegally as Ultan Dillane was guilty of a no arms tackle; from the free play Zebo had tried to find Keith Earls but he was knocked on when tackled by Niyi Adeolokun.
Back we came for the penalty, though and, spurning the posts, the decision to kick the corner paid dividends as, from Billy Holland's unchallenged take, Mike Sherry led the charge for the line and was carried there by his team-mates to collect his side's second try.
Holland was having a terrific game and his touch line conversion was a thing of beauty, perfectly weighted to drift with the wind and give his side a 14-6 advantage after 25 minutes.
Connacht responded brilliantly but they wasted a great opportunity when Kieran Marmion dropped Aki's pass after the combative centre had burgled his way past Tommy O'Donnell's tackle attempt.
They returned to the 22 almost immediately but Billy Holland turned the ball over when his side were in dire peril - referee Whitehouse was hot on players not releasing and when an electric Matt Healy break ended in another Munster penalty, the crowd hooted their derision and despair.
They changed their tune moments later when the referee lost patience with the permanently imploding scrums and he sent Cronin to the bin for the final eight minutes of a half that was speeding by.
Connacht needed to pounce and they did from the resultant kick to touch in the 22 - eventually. After going from side to side, and then backwards with a poor Adeolokun pass, suddenly the jaded attacking structure breathed new life as Munster stepped off.
Aki ran back from the ten metre line, made a typical bust and, when Finlay Bealham produced a delicious off-load, there was that man Adeolokun to make amends for his earlier error to gleefully scamper beneath the posts.
O'Leary's conversion reduced the margin to 14-13.
Connacht were roaring and Aki was rampaging, intercepting a Holland pass to make 50 metre as Munster wilted under the resurgent home side's pressure. Awarded a penalty, captain John Muldoon opted for a scrum.
They didn't get in for the score but Munster lost another man to the bin when Billy Holland was yellow-carded for a cynical offence as the clock went dead.
Connacht's only option was a scrum with the clock in the red; soon Munster were in the red as An inevitable surge from the push gave Whitehouse no option but to award the penalty try. O'Leary's facile conversion completed the dramatic turnaround - from 14-6 behind to 20-14 ahead in just 15 minutes.
Munster restarted the second-half with 14 men and an early turnover in Connacht's 22 gave them hope of playing down the second sin-binning clock. They spent that time in the 22 but rarely threatened as the 7,786 capacity crowd throatily roared defiance.
Billy Holland's return restored the numerical parity but in the fifteen minutes that his side had been disadvantaged, Connacht had managed to completely turn this game on its head. Munster's discipline did not show signs of improvement and they allowed the home side to retain their forward momentum.
Then, in the 54th minute, Connacht sprung for their third try, all began with a beautiful back-line move involving screen pass from Marmion that set Robbie Henshaw down the right wing.
He kicked a grubber that utterly bamboozled Darren Sweetnam, who suddenly seemed so startled it was if If he had located a rogue icy patch; despite Zebo's desperate cover, he only succeeded in knocking the ball into the onrushing Adeolokun's grasp and he nabbed his second of an enthralling evening.
It was now 25-14 and, with Sweetnam hauled off, despite receiving just one pass all day before seeing his replacement Andrew Conway pass his first ball straight into touch, Connacht certainly could not throw away this advantage despite the still vivid memories of their dramatic collapse in Grenoble seven days ago.
As the game entered the final quarter, Munster earned themselves a five-metre lineout after a previous effort had been illegally sacked; eventually, Francis Saili attempted a spectacular swan dive scoring attempt by diving over a goal-line ruck.
Unfortunately for Munster, the TMO confirmed that he had dropped the ball before regathering for what he had hoped, so desperately, might have been a resuscitative score.
Connacht, liberated, broke to the halfway line through the indefatigable Aki, defying a troublesome knee, before winning a crucial scrum penalty which brought them back 30 metres within scoring range.
Ultan Dillane nearly made the entire distance himself before Connacht patiently worked themselves into a position for Finlay Bealham to score the decisive try which garnered the bonus point.
A late penalty from Shane O'Leary added a grace note. But nobody told the Connacht Clan, who remains singing long after the final whistle had signalled the end of another tumultuous, ground-breaking night for rugby in this once impoverished arena.
Connacht - R Henshaw; N Adeolokun, B Aki, P Robb (J Carty 74), M Healy; S O'Leary, K Marmion (J Cooney 67); D Buckley (R Loughney 74), T McCartney (J Harris-Wright 74), F Bealham (JP Cooney 68), U Dillane, A Muldowney (A Browne 64), S O'Brien (J Connolly 72), E McKeon, J Muldoon capt.
Munster - S Zebo; D Sweetnam (A Conway 56), F Saili, R Scannell, K Earls; J Holland (I Keatley 67), C Murray; J Cronin (D Kilcoyne 56), M Sherry (N Scannell 56), S Archer (J Ryan 68), D Ryan (J Coghlan 70), B Holland, CJ Stander capt, T O'Donnell, J O'Donoghue (R Copeland 56).
Ref - B Whitehouse.