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.
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)