Northampton had an historic victory snatched from their grasp as a late drop-goal from Ronan O'Gara saw Munster win 23-21 at Thomond Park.
Saints had looked to be heading to a vital Pool win even at such an early stage in the campaign. But with the scores at 20-21, Munster launched a 40-phase attack before Limerick favourite O'Gara sat back in the pocket and ultimately did the rest.
Last year's runners-up, Northampton, must have thought they had done enough to claim a rare away win at Thomond Park when tries from Chris Ashton and James Downey and eleven points from Ryan Lamb's boot put them two points up.
But, after first half tries from Damien Varley and Doug Howlett had kept Munster in contention, it was O'Gara, whose kick at the death, that won it.
It was Munster who started brighter with Varley going over with just three minutes on the match clock. It was a statement from the young side.
Saints hit back though almost immediately when wing Ashton went over after great work from Ben Foden. Lamb converted and then hit two further first half penalties.
Northampton were then stunned by the first of two late-half spells from Munster, the first seeing Howlett break the line and O'Gara convert to send the hosts into the sheds ahead.
O'Gara then drew first blood in the second 40 with three points before Lamb responded with one of his own three minutes later at the special venue, which was lapping up the spectacle.
Then came another example of Northampton's power up front, particularly at scrum-time, as their strong platform allowed former Munster centre Downey to dummy and go in untouched. Playmaker Lamb missed the extras but Saints were ahead until the dying embers.
Cue Munster drawing on all of their European experience and with 40 phases amassed, O'Gara sat back and knocked over a sweet drop-goal for victory.
Tries: Varley, Howlett
Con: O'Gara 2
Pen: O'Gara 2
Tries: Ashton, Downey
Pen: Lamb 3
Munster: 15 Johne Murphy, 14 Doug Howlett, 13 Danny Barnes, 12 Lifeimi Mafi, 11 Denis Hurley, 10 Ronan O'Gara, 9 Conor Murray, 8 James Coughlan, 7 Niall Ronan, 6 Peter O'Mahony, 5 Paul O'Connell, 4 Donnacha Ryan, 3 BJ Botha, 2 Damien Varley, 1 Wian du Preez.
Replacements: 16 Denis Fogarty, 17 John Ryan, 18 John Hayes, 19 Donncha O'Callaghan, 20 Denis Leamy, 21 Tomas O'Leary, 22 Ian Keatley, 23 Will Chambers.
Northampton: 15 Ben Foden, 14 Chris Ashton, 13 Jon Clarke, 12 James Downey, 11 Vas Artemyev, 10 Ryan Lamb, 9 Lee Dickson, 8 Roger Wilson, 7 Tom Wood, 6 Calum Clark, 5 Mark Sorenson, 4 Courtney Lawes, 3 Brian Mujati, 2 Dylan Hartley, 1 Soane Tonga'uiha.
Replacements: 16 Mikey Haywood, 17 Alex Waller, 18 Paul Doran-Jones, 19 Samu Manoa, 20 Phil Dowson, 21 Martin Roberts, 22 Steve Myler, 23 George Pisi.
Referee: Nigel Owens (Wales)