Fortune never favoured brave Galway United at Terryland Park as Sean Francis scored twice late on to add to the home's side misery after they had gifted Rovers the lead and missed a penalty.
In truth, Rovers were flattered by the win, never mind the scoreline, which took them to second in the table, as they never really played with any fluency against a Galway side eager to build on last week's excellent win at Dalymount Park.
Having wasted several good openings in the first-half, it all began to go sour for Galway nine minutes after the interval when stand-in right-back Ollie Keogh needlessly gave the ball away to Brian Byrne who raced away, played a one-two with Graham Lawlor to tap home from six yards.
That was harsh on Keogh and Galway, who played well, as the home side controlled much of the game. A glorious opportunity to level on 71 minutes then went abegging, however, when Kieran Foley was pulled down by Terry Palmer.
Transfer-listed Eric Lavine stepped up only to see his spot kick parried by Tony O'Dowd with Palmer redeeming himself by scrambling the loose ball out for a corner.
To add insult to injury, Foley headed the ball home from Adrian Cregg's corner only for Dublin referee Eddie Barr to disallow it for pushing.
As it transpired, Rovers went 2-0 up within a minute when Francis scored the first of his brace when chipping David Forde from some 20 yards.
Francis then ran clear of a pressing Galway to complete this undeserved Rovers victory to shoot low past Forde two minutes from time.
GALWAY UNITED: Forde; Keogh, O'Connor, Morgan, Quirke; Malee, Dolan, Keane, Ogden; Foley, Lavine. Subs: Cregg for Malee (67 mins.), Goldbey for Foley (76 mins).
SHAMROCK ROVERS: O'Dowd; Brazil, Purdy, Palmer, Dunne; Robinson, Colwell, Kenny, Byrne; Francis, Lawlor.
Referee: E Barr (Dublin)
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