Shamrock Rovers bounced back from last Monday's Dublin derby defeat to Bohemians by recording a 1-0 win over a Waterford side that were undone by a huge mistake by goalkeeper Stephen McMullan late in the second half.
It looked like the game, which was a lacklustre affair, was heading for a stalemate until McMullan allowed a Danny Mandroiu long-range speculative shot to spill from his grasp in the 74th minute and substitute Rory Gaffney gleefully turned the loose ball into the net.
In the end, the Gaffney goal was enough for Rovers, who emerged victorious for the third time this season against the visitors following a 3-1 win at the RSC last month, adding to their 2-0 victory in Tallaght back in April.
Before kick-off, Rovers manager Stephen Bradley had continued to rotate his squad, making changes from the defeat to Bohemians last Monday, starting Mandroiu in midfield instead of Aaron McEniff, while Jack Byrne made way for Dylan Watts, with teenager Michael Noonan replacing Aaron Greene up front.
Waterford head coach John Cousins made one change from the draw with Shelbourne as veteran Andy Boyle, who made his first appearance since April on Monday night at the RSC in the 2-2 draw against Shelbourne, started in defence.
Rovers had started the tie well, and in the fifth minute, Graham Burke's cross found its way to the back post to Danny Grant, who, off balance, stroked his effort off the butt of the Blues post.
Moments later, Grant returned the favour, setting up Burke inside the area, but Burke could not keep his shot down.
As it was, Waterford should have hit the front with their first real attack, as just after the quarter-hour, Jesse Dempsey's left-wing cross found Olajinka in the area, and who should have scored, but his side-footed shot was brilliantly saved by Hoops Keeper Ed McGinty.
At the other end, McMullan denied Josh Honohan, diving to his left as the Rovers winger tried to bend his shot into the net from just inside the area.
McMullan also got his fingers to a long-range Mandroiu effort on the half-hour, tipping the shot over for a Hoops corner which came to nothing.
Late in the half, a poor Boyle header went straight to Mandroiu on the edge of the area, who in turn set up Burke, whose snapshot was narrowly wide with McMullan beaten.
Waterford set up shop in the second half as Rovers huffed and puffed in their efforts to get the opening goal, but the Blues defence was solid, only allowing half-chances for Holohan and Noonan as they scrapped for a point.
However, the visitors conceded with 16 minutes to go as Mandroiu’s shot should have been dealt with by keeper McMullan.
Instead, and to the goalkeeper's horror, he let the ball bounce off his chest, and Gaffney turned the ball into the empty net.
Shamrock Rovers: Ed McGinty; Daniel Cleary, Roberto Lopes, Lee Grace; Danny Grant, Dylan Watts (Rory Gaffney 65), Danny Mandroiu (Gary O’Neill 87) Josh Honohan; Graham Burke (Jack Byrne 65), Mathew Healy (Victor Ozhianvuna 75); Michael Noonan (Darragh Nugent 87).
Waterford FC: Stephen McMullan; Grant Horton, Andy Boyle, Daragh Leahy, Ryan Burke (Trae Bailey Cole 79), Jesse Dempsey (Kyle White 71); Thomas Lonergan, Rowan McDonald (Dean McMenamy 68), Olujimi James Ayodele Olayinka, Samual Glenfield; Pauric Amond.
Referee: Paul Norton.
