The Limerick captain rose highest in the box after 25 minutes to powerfully head home a Shane Tracy corner.
Gary Keane almost rescued a point for the Blues in injury-time but to no avail.
LIMERICK FC: Ryan, Tracey, Frost, Purcell, O’Callaghan, Judge, O’Leary (White 80) Quinn (Coughlan 72) Tracy, Hynes, O’Flynn (O’Connor 83)
WATERFORD UTD: Burns, Chin (Dunphy 77) Cody, Murray, Browne, Breen, Dempsey (Nolan 52) Kiely, Murphy, Keane, Sinnott (Wilson 69Kg)
Referee: K O’Regan (Kerry).
By John Fallon
TOM KING struck twice to secure victory for Mervue United at Fahy’s Field as Finn Harps’ quest for a first win continues after 10 games.
King’s header gave Mervue the lead on 37 minutes. Marc Brolly equalised 10 minutes after the restart with a free.
King struck the winner seven minutes from time, chipping Ciaran Gallagher.
MERVUE UNITED: Hanley (Forde, 45); Casserly, Conneely, Crehan, Cunningham; King, Ludden (Goldbey, 84), Tierney (Mountney, 67), Varley; Gaffney, Molloy.
FINN HARPS: Gallagher; Cowan, Doherty, Mailey, McLaughlin; Bonnr, Brolly, Conaghan (Merritt, 85), Forker; Friel, McHugh.
By Brendan Furlong
THREE second-half goals gave bottom side Salthill Devon three deserved points over fellow strugglers Wexford Youths at Ferrycarrig Park last night.
Wexford went ahead on 45 minutes when Ben Ryan fired home.
Salthill equalised on 67 mnutes through Patrick Quinlan and went ahead with a Victor Collins goal on 76 minutes. Ciprian Strout got the third in injury-time.
WEXFORD YOUTHS: Holden, McCurtain (Wolfe 73), Broaders, Keogh, Kehoe, Malone, Ryan, Wall, Furlong, Grincell (Walshe 53), Nolan (Rowe 63).
SALTHILL DEVON: Forde, Quinlan (Quirke 78), O Ceidhin, Whelan, Fadden, O’Brien, Grenath, Browne, Collins (Dolan 81), CStrout, Nololo.
Referee: D McKeon (Dublin).