SHANNON 6 GARRYOWEN 31, Coonagh
Scorers: Shannon: Pen: David O'Donovan; Drop: Mossie Lawlor
Garryowen: Tries: David Sherry, Kieran Lewis, Conan Doyle, Keith Earls; Con: Alan Kingsley; Pens: Conor Kilroy 3
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A crowd of over 2,000 crammed into the Limerick venue to watch the defending champions put their great rivals to the sword.
Playing with a strong wind, Garryowen built up a 14-3 half-time lead with replacement David Sherry's 35th-minute try topping off three penalty kicks from full-back Conor Kilroy.
Mossie Lawlor had landed an early drop goal for the hosts.
A penalty from Shannon winger David O'Donovan cut the gap to eight points and the same player was unfortunate when another monster penalty attempt bounced back off the left upright.
But Garryowen's pack exerted greater control and tries from Munster-capped backs Kieran Lewis, Conan Doyle and Keith Earls saw the visitors pull decisively clear.
Eight-time league winners, Shannon were hoping to maintain their end of season push for honours after their recent AIB Cup success.
This was the host club's sixth Division One semi-final and had won all five of their previous semis - four of them at their regular home ground of Thomond Park.
Coming into this game, Mick Galwey's side had won their last eleven home fixtures in the league. However, in the sky blue corner, were a Garryowen team that had chalked up a club record run of ten league wins.
Dara O'Sullivan's well-drilled outfit were bidding to hold their league title, the only piece of silverware left available to them after Shannon's Munster Senior Cup and AIB Cup successes.
And they managed to do just that with an excellent performance which saw their forwards outplay their Shannon counterparts, while their backs showed off their finishing skills.
The victory was all the more impressive given that Garryowen had lost their inspirational flanker and captain Paul Neville to a shoulder injury in the first half.
As a measure of the squad strength at O'Sullivan's disposal, Neville's replacement Sherry popped up to score a timely try towards the end of the first 40 minutes.
Whereas Shannon had a number of their Munster-contracted players ineligible and unavailable for the derby tie, Garryowen's clever management of their players throughout the season meant they could start with Munster's Kieran Lewis and Keith Earls in their back-line.
Fleet-footed winger Earls recovered quickly from the stomach bug that kept him out of Munster's midweek defeat to Ulster to play an influential role at Coonagh.
He was electric with ball in hand and was afforded a number of opportunities to attack the Shannon line, while the hosts' chief threat out wide, pacy Limerick footballer Stephen Kelly, was largely nullified.
Predictably, with that wind behind them, Garryowen made the early running and after AIB man-of-the-match Peter Malone and Ciaran O'Boyle had been stopped short of the Shannon line, out-half Willie Staunton missed with a third-minute drop goal attempt.
Full-back Conor Kilroy landed a ninth-minute penalty to nudge Garryowen in front but their lead lasted only two minutes as Lawlor picked off an opportunistic drop goal after an overthrown lineout from Sean Cronin.
Shannon's discipline was poor however, as the tension got to David Quinlan and company particularly in the second half.
After infringements by Phil O'Connor (17 minutes) and Colm McMahon (25), Kilroy kicked the visitors into a 9-3 lead.
Their first try then came out nothing. Staunton hoisted up a garryowen, Shannon let it bounce and Lewis linked with Mark Melbourne before a cut-out pass from Staunton put Sherry stretching over to the left of the posts.
Kilroy missed the conversion, leaving Shannon with a 14-3 deficit to overcome in the second half.
Turning around with the elements, the 2006 champions cut the gap to eight points with a cracking left-sided penalty from O'Donovan.
He agonisingly missed with an attempt from inside his own half and with Garryowen lock Melbourne brilliantly running the ball back to the ten-metre line, that was the game's defining moment.
Garryowen soaked up anything Shannon could throw at them, despite the best efforts of Lawlor, Quinlan and John Clogan.
On 58 minutes, after a sustained bout of pressure from the visitors' pack, centre Lewis touched down in the left corner, getting over on the drift past O'Loughlin.
With O'Donovan then sin-binned for a foolish stamp on Anthony Kavanagh, Garryowen clinically saw out the result with two late tries.
Centre Conan Doyle dashed in behind the posts in the 73rd-minute after Staunton had made a half-break and popped a pass to him.
Kilroy missed the conversion but it was the tries that were killing Shannon and Earls wrapped up the win with a superb solo effort in the 79th-minute.
The Munster wide man picked up a loose ball at the back of a scrum, beat two men initially and went on a 40-metre burst evading O'Donovan's last gasp tackle before touching down. Replacement Alan Kingsley tapped over the simple conversion.
Garryowen were home and dry and with Cork Constitution - the side they beat in last year's decider - their opponents again in next Sunday's final (Musgrave Park, kick-off 1.15pm), they will be confident of a repeat win.
SHANNON: Andrew Finn; David O'Donovan, Mike Kinsella, John Clogan, Stephen Kelly; Mossie Lawlor, Fiach O'Loughlin; Killian O'Neill, Sean Cronin, Kevin Griffin, Padraic O'Brien, Fergal Walsh, Phil O'Connor, Colm McMahon, David Quinlan (capt).
Replacements used: Joe Manuel for Clogan (57 mins), Les Hogan for O'Neill (58), Leonard Mullane for O'Connor (60), Eoghan Grace for O'Brien (70), Andrew Thompson for Finn (76).
GARRYOWEN: Conor Kilroy; Cillian O'Boyle, Kieran Lewis, Conan Doyle, Keith Earls; Willie Staunton, Gerry Hurley; Rory Brosnan, Damien Varley, Eugene McGovern, Mark Melbourne, Frank McKenna, Paul Neville (capt), Anthony Kavanagh, Peter Malone.
Replacements used: David Sherry for Neville (29 mins), Declan Lavery for Brosnan (76), Lorcan Bourke for Kilroy, Alan Kingsley for Staunton (both 77), Federico Quaglia for Lewis (78).
Referee: Simon McDowell (IRFU)