Captain Ian Bermingham and Paul O'Conor provided first half goals, and palpable relief around Richmond Park, to give St Patrick's Athletic a major lift in every sense.
The much needed victory, their second over Shamrock Rovers in the SSE Airtricity League Premier Division this season, raises Liam Buckley's side two places out of the relegation zone and two points clear of the bottom three.
Both sides made changes from Friday night with Bermingham returning at left-back for St Patrick's while O'Conor came into their midfield as Graham Kelly dropped back into right-back for Michael Barker.
Dave Webster, Ryan Connolly and Gary Shaw all returned to Rovers'starting line-up.
After a cagey opening it was Hoops' striker Shaw who brought the game to life on 10 minutes.
Connolly got free on the right to whip over a cross for Shaw whose glancing header came out off the crossbar.
Two minutes later Brandon Miele found space on the edge of the area to set up Cameron King whose low drive was palmed away by Saints' keeper Lukasz Skowron.
St Pat's worked their way into the game, creating a opening on 16 minutes. Conan Byrne cleverly cut past a defender to get off a shot which was bravely blocked by Webster.
Encouraged by that, St Pat's were in front three minutes later.
Killian Brennan took a free kick short to Byrne on the right flank and his precise delivery off his weaker left foot was met by Bermingham who planted a looping header past Tomer Chencinski to the net.
Rovers remained threatening when they got forward and might have levelled on 28 minutes.
Right-back Simon Madden's cross wasn't dealt with by the Saints' defence. The ball dropped to Shaw whose bicycle kick lacked the power to trouble Skowron.
Frantic defending back at the other end then prevented St Pat's doubling their lead on the half hour. Christy Fagan was left unattended at the back post, but Roberto Lopes got back to make a superb block.
From the resulting corner, the ball fell for Owen Garvan on the edge of the area. The midfielder got right under the ball to power his shot well over the top.
St Pat's then survived a right scare on 39 minutes.
Shaw showed tenacious pace to get past Lee Desmond on the right to cross low from the end line. King stretched to reach the cross only to see his scrambled effort cleared by Jordi Balk.
But it was St Pat's who added to their lead three minutes before the interval.
Byrne was again central to Saints' attacking play. The dynamic winger put over a deep cross from the right and O'Conor arrived at the near post to score with a downward header for his first goal for the club.
Connolly should have pulled a goal back for Rovers in first half stoppage time, but was thwarted by Skowron who parried the shot away for the save of the first half.
James Doona, on for Rovers from the start of the second half, worked Skowron on the hour with Shaw's follow up deflected for a corner.
Skowron then excelled a minute later, brilliantly tipping a header from Lopes from Simon Madden's cross onto the bar and away.
The Polish keeper proved his worth once again on 78 minutes, batting over Hoops' skipper Ronan Finn's powerful drive from distance.