Cork City took the spoils in a Munster derby that Irish soccer historians would be best advised to speed type into the footnote section.
The first moment of genuine quality in an eircom League of Ireland Premier Division match virtually devoid of incident to that point arrived in the 40th minute, and it gave Damien Richardson's side the lead.
Cutting inside Robbie Hedderman from the right edge of the penalty area, Gareth Farrelly steered a terrific left-footed shot beyond the diving Dean Delaney into the top corner.
While the public address informed fans that this was a Category A fixture, the fare on the pitch below was anything but in what had to rank as one of the most unremarkable halves of the season.
Some Waterford fans were not even back in their seats by the time Cork had doubled their lead less than a minute into the second half.
Colin Healy's deep free kick hardly reeked of danger upon delivery, but nonetheless found its way to the unchallenged Dan Murray who swept the ball home from six yards.
United ought to have got back into the match on 63 minutes, after Alan Kearney's deflected pass left fellow substitute Willie John Kiely with a goal at his mercy from eight yards. But, to the groans of the home support, Kiely pulled his shot wide.
Four minutes from time, Cork wrapped up the points which keep them in contention for a European berth.
Availing of the space afforded him down the right flank, Leon McSweeney steered the ball across the six-yard box to the waiting Joe Gamble who nodded in from point-blank range.
The first time either side came close to making a breakthrough arrived after 18 minutes, when Liam Kearney’s jinking run and pass put Farrelly in space down the right.
The ex-Irish international struck a dangerous ball across the Waterford goalmouth, but there was no Cork jersey in sight to apply the finishing touch.
United's first attack of note took 28 minutes to arrive, when Karl Bermingham turned inside Neal Horgan on the left flank and into the penalty area. But his final ball was blocked and cleared to safety by the visiting defence.
While Cork's hopes of a second place finish remain realistic, Waterford ended the night back in the relegation zone.
The forthcoming fixtures with Bray Wanderers and Galway United are now looming ominous for Gareth Cronin's side.
Waterford United: Delaney, Flynn, Hedderman, D Mulcahy, Breen, Scully, Warren (A Mulcahy, 72 mins), McCarthy (A Kearney, 59), Sullivan, Kavanagh, Bermingham (Kiely, 55).
Cork City: McNulty, Horgan, O’Callaghan, Murray, Ryan, Farrelly, Healy, J Gamble, L Kearney (Woods, 78), O’Flynn, McSweeney.
Referee: D McKeon (Dublin).
