Mark McGinley proved the Finn Harps hero for the second week running, producing superb saves to frustrate Longford Town at Bishopsgate.
An own goal and strikes from Ryan Rainey and Sean Boyd did the damage at the other end.
Following their win at Sligo Rovers last week, back-to-back victories lifts Harps out of the relegation play-off place, a point ahead of Waterford with a game in hand.
Longford's miserable season thus continues as they now slump 14 points adrift at the bottom without a win in 23 games since the opening night of the season.
With an overriding sense of it being a stage of do or die for their Premier Division survival, Longford came out pumped up, getting themselves on the front foot from the start.
Paddy Kirk dashed down the left flank two minutes in to whip over a deep cross that came back off McGinley's crossbar.
The danger remained with Dean Williams setting up Rob Manley whose drive cannoned away off a defender.
Harps held firm to threaten themselves three minutes later.
Town struggled to defend a throw on the right with the ball running for Dan Hawkins whose thumping shot from 20 yards was bravely blocked by Aaron Dobbs.
With the game maintaining its energetic start, a Manley cross forced some frantic defending back at the other end as the visitors eventually cleared their lines.
Longford’s defending was as desperate minutes later, Tunde Owolabi collecting Barry McNamee’s ball in space in the box to see his shot deflected out for the first corner of the night.
It was then the turn of the home goal frame to be rattled when Will Seymore’s shot bounced off Lee Steacy’s crossbar.
But Harps would be rewarded for their spell of pressure with a deserved lead on 14 minutes, if there was an element of good fortune to it.
Ryan Connolly put Jordan Mustoe in behind Aaron McNally on the left.
The full-back’s innocuous enough low cross struck Town centre-back Mick McDonnell on the heel to wrong foot Steacy and fly into the corner of his net for an own goal.
Harps continued to look dangerous every time they got forward with Steacy better positioned to save a stinging shot from Mustoe on 21 minutes after good approach play from Owolabi and Hawkins.
But it was McGinley who would produce the save of the game on 34 minutes to keep Harps ahead.
Aaron McNally’s deep cross from the right ran through for Dylan Grimes. His lay off set up midfield anchor Aodh Dervin to crack a shot from distance which saw McGinley go full stretch to his left to push the ball round a post for a truly brilliant save.
It proved pivotal as three minutes later Harps doubled their lead.
McNamee’s corner wasn’t fully cleared by the home defence. And when the ball dropped invitingly for Rainey just outside the area his terrific right-footed volley took a slight nick off a defender to arrow into the top corner.
Owolabi headed over from substitute Adam Foley’s cross five minute into the second half as Harps wasted an opening to extend their lead.
While there was no faulting Longford’s effort, the midlanders couldn’t find a way past McGinley who made his second telling save of the game on 53 minutes.
Dervin found McDonnell, who had remained up following a corner, in space in the area. McGinley spread himself superbly to save the shot with his feet.
McGinley was then perfectly positioned to hold an Aaron O’Driscoll header on his line following a Grimes free kick.
In a far from fractious game, referee Derek Tomney’s yellow card hit double figures including a red for Harps’ manager Ollie Horgan, a second caution for dissent.
Boyd then added the third goal when heading home McNamee’s corner on 84 minutes.
Longford Town: Lee Steacy; Aaron McNally, Mick McDonnell, Aaron O’Driscoll, Paddy Kirk; Aodh Dervin, Darragh Nugent; Rob Manley, Dean Williams (Callum Warfield 63), Dylan Grimes (Conor Davis 74); Aaron Dobbs (Aaron McCabe 88).
Finn Harps: Mark McGinley; Dave Webster, Kosvar Sadiki, Shane McEleney, Jordan Mustoe; Ryan Connolly (John Dunleavy 70), Will Seymore; Ryan Rainey (Joel Bradley 90+1), Barry McNamee, Dan Hawkins (Adam Foley h-t); Tunde Owolabi (Sean Boyd 78).
Referee: Derek Tomney (Dublin).