As they now prepare for next week's Conference League opener against Swedish side BK Häcken, Harry Wood produced another big goal to keep Shelbourne's quest for European football next summer very much alive.
Attacking midfielder Wood, who scored the goal that clinched the league title last season, capped another fine display in red with a late penalty to undo dogged Waterford.
Though Shelbourne remain sixth in the table, they’ve narrowed the gap to third to four points with a game in hand.
A fifth successive defeat means Waterford, top of the table after four games in early March, slip to second bottom and into the relegation play off place.
With no fewer than five changes from the side beaten in Drogheda on Monday, Shels were lively from the kick off and ahead after seven minutes.
Kerr McInroy was the orchestrator with a sublime pass over the top beyond defender Grant Horton for the incisive run of Ali Coote.
The Scot took a controlling touch to cut inside to arrow his right-foot shot to the roof of the net for his fifth goal of the season.
Shels cut Blues open all took easily again on 10 minutes.
Milan Mbeng worked a neat one-two with Coote only to undo his good approach play by blazing over the top.
The home fans were soon baying for a penalty when Sam Glenfield ended Coote’s galloping run, though the trip was rightly ruled just outside the area.
Waterford gradually played their way into the game and troubled Shels from a series of corners before levelling on 42 minutes.
James Olayinka linked with Jesse Dempsey on the left with the low cross superbly turned home first time by Conan Noonan for a well-taken sixth goal of the campaign.
As with the first, Shels started the second half on the front foot, an upright and a fine save prevented them from regaining the lead eight minutes in.
A quick free-kick from Wood put John Martin away on the right. His low cross came back off the far post to set up James Norris whose shot was brilliantly parried away by Stephen McMullan.
The young Blues keeper was there again to tip a Sam Bone drive round a post as Shels’ pressure mounted.
Evan Caffrey skied over the top from fellow substitute Dan Kelly’s cross while Coote blasted off target as the visitors’ goal led a charmed life as Shelbourne searched for a winner.
It finally came on 79 minutes with Wood the instigator and finisher.
The Yorkshire man’s initial free kick saw Paddy Barrett tripped inside the area to concede a penalty.
Wood sent McMullan the wrong way from 12 yards for his third goal in four games and eighth of the season.
A big save from Wessel Speel from Padraig Amond was needed within a minute, the Waterford skipper rifling the rebound just wide before Sean Gannon hacked off the line from Tommy Lonergan deep in stoppage time as Waterford left Drumcondra empty-handed.
Shelbourne: Wessel Speel; Sam Bone (Sean Gannon 90), Paddy Barrett, Kameron Ledwidge; Milan Mbeng (Dan Kelly 60), JJ Lunney (Jack Henry-Francis 68), Kerr McInroy (Sean Boyd 77), James Norris (Evan Caffrey 60); Ali Coote, Harry Wood; John Martin (Mipo Odubeko 68).
Waterford: Stephen McMullan; Grant Horton (Muhammadu Faal 90+1), Kacper Radkowski, Ryan Burke; Joshua Miles (Ronan Mansfield 74), Jordan Rossiter, Sam Glenfield (Tommy Lonergan 49), James Olayinka, Jesse Dempsey (Kyle White 59); Conan Noonan; Padraig Amond.
Referee: Marc Lynch (Galway).
