Conan Byrne 45' -
A solitary goal from Conan Byrne just before the half-time interval was enough to see St.Patrick's Athletic prevail to their second Leinster Senior Cup final in a row.
In a repeat of last year's final, Rovers made the short journey to Dublin 8 looking to reach their third consecutive Leinster Senior Cup final.
Pat's on the other hand were hoping to avenge last year's final defeat and reach back-to-back finals in this competition with a second win of the season over their southside rivals.
In contrast to the hosts who fielded an experienced first eleven with the exception of youngsters Sean Hoare and Sam Verdon who were afforded the chance to impress by manager Liam Buckley, Rovers fielded their First Division squad for this encounter with Colin Hawkins and Noel White manning the away dugout in place of the absent first-team management duo of Trevor Croly and John Gill.
It was Pat's who enjoyed the better of the opening exchanges with them enjoying the upper hand in the early half possession steaks.
Killian Brennan and Daryl Kavanagh both went close inside the first ten minutes on two occasions each, however neither could keep their body over the ball enough to test Shane Fagan in the Rovers goal.
Brennan was of particular threat to the Tallaght Stadium outfit's rearguard and on twenty-five minutes he went agonisingly close to breaking the deadlock with a trademark free-kick that rattled Fagan's upright.
Rovers failed to clear the ball to safety and so a second Saints near miss followed almost immediately. On this occasion the ball broke to another ex-Hoop, Daryl Kavanagh after Shane Fagan failed to hold a Brennan cross, however Corie Tracey scampered back to scramble away the Tipperary man's poke toward goal.
The Richmond Park side's dominance did eventually pay dividends with Conan Byrne tapping home the opener shortly before half-time. Brennan was again instrumental, this time clipping the ball toward the back post for Mark Quigley to delicately nod the ball into the path of Byrne who made no mistake from close range.
Despite being outplayed by more experienced opposition for the best part of the opening forty-five, Hawkins' youthful Shamrock Rovers charges could not be accused of showing a lack of endeavour.
Their efforts were almost rewarded with an immediate equaliser in the closing minutes of the first- half with Rene Gilmartin being forced to parry Daniel Purdy's pile driver after Mark Sandford laid the ball into the path of the former Irish underage international.
Despite St. Pat's opening the second-half with the same monopoly over possession they held in the opening half, Liam Buckley's side struggled to establish a fluidity in their offensive play conducive to the creation of goalscoring opportunities.
Chris Forrester entered the fray on fifty-six minutes, however the recently voted SWAI Player of the Month struggled to find the space he required to make use of his creative prowess.
So consumed by a midfield battle was the vast majority of the second period that those in attendance at Richmond Park had to wait almost half an hour for the half's first real clear cut opportunity to be created.
Daniel Purdy was again the main instigator of the Hoops' attacking threat with the former Longford Town man slipping in substitute Azeez Yusuff. Unfortunately for the visiting support, Yusuff wasted a golden opportunity to draw Rovers level by blasting his effort high over Gilmartin's crossbar.
With just a minute of injury time remaining, Mark Quigley almost put victory beyond all doubt for St.Pat's, however the former Rovers striker's effort curled wide of the Shed End goal's left hand post.
Quigley's miss was to be the last significant action of the game and so the St.Pat's players left the Richmond Park turf having sealed progression to a Leinster Senior Cup final showdown with Longford Town.
St Patrick's Athletic: Rene Gilmartin; Conor McCormack, Sean Hoare, Ken Oman, Lorcan Fitzgerald; Conan Byrne (Lee Lynch 46), Greg Bolger (James Chambers 50), Killian Brennan, Mark Quigley; Sam Verdon (Chris Forrester 52), Daryl Kavanagh.
Subs not used: Brendan Clarke (gk), Ger O'Brien, Kenny Browne, Peter Durrad.
Shamrock Rovers: Shane Fagan; Liam Traynor, Conor Dunne, Corie Treacey, Evan Osam (Kehoe 63); Adam Whelan (Muhanned Bukhatwa 78), Ryan Doolin, Jack Watson, Daniel Purdy; Mark Sandford (Yusuff 69), Cian Kavanagh.
Subs not used: Michael Kelly (gk), Nathan Brown, Richard Purdy, Kevin Knight..
Referee: Simon Rogers (Dublin)
Attendance: 750 (estimate)
ExtraTime.ie Man of the Match: Killian Brennan (St Patrick's Ath)