Gary McCabe scored a well-taken first half brace as Shamrock Rovers took the points at Tallaght Stadium in a 2-1 win to give Trevor Croly's Hoops a second successive Premier Division win.
Cork, out of sorts in the first half, responded in the second 45 minutes to make a match of it with a goal from Garry Buckley, though Rovers had done enough to edge to within three points of fourth-placed Derry City, though with a game more played.
With Ciaran Kilduff ineligible due to his being on loan from Rovers, Cork gave a first league start to Stephen Kenny in partnering the in-form Danny Morrissey up front.
Despite being hit with suspensions and injuries, Rovers, with five changes to the side that beat Shelbourne last week, started brightly with Billy Dennehy and Ronan Finn having chances before they deservedly took the lead on nine minutes.
Dennehy’s low cross in from the left saw Tommy Stewart flummox Buckley with a delightful turn in the box to set up McCabe to sweep the ball home from close range.
It took Cork almost 20 minutes to register an effort on goal, Daryl Horgan rifling just over the Barry Murphy’s crossbar from some 30 yards.
But Rovers responded to double their lead within three minutes.
Dennehy’s dummy from skipper Shane Robinson's ball outwitted Cork captain Dan Murray to give McCabe a clear run in on goal.
And the winger, relishing playing in the hole in a 4-4-1-1 formation, showed sparkling composure to side-foot past Mark McNulty to the corner of the net.
Gearoid Morrissey lifted the pressure on Cork when firing wide just past the half hour. But it was Rovers who should have gone further ahead on the counterattack on 36 minutes.
Pat Sullivan fed Dennehy on the right and his low cross was hit first time by McCabe who held his head in his hands as McNulty made a super reflex save to deprive him of his hat-trick.
But Stewart should rally have given Rovers a 3-0 lead in the final minute of the half. Played in behind the shocking Cork defence by McCabe, Stewart raced in only to drill his shot wide across goal.
Cork made changes at the break and made a match of it on 67 minutes when getting a goal back.
Ian Turner whipped over a corner from the left and Rovers defence was found wanting as Buckley rose well to score with a powerful downward header.
Rovers defended well thereafter with McCabe having a late chance for his third of the night in stoppage time only to blaze over the bar.
Shamrock Rovers: Barry Murphy; Pat Sullivan, Ken Oman, David Elebert, Conor Powell; Ronan Finn, Richie Ryan (Stephen Rice 82), Shane Robinson, Billy Dennehy (Sean O'Connor 71); Gary McCabe; Tommy Stewart
Cork City: Mark McNulty; Neal Horgan, Dan Murray, Garry Buckley, Danny Murphy; Gearoid Morrissey, John Dunleavy (Colin Healy h/t), Shane Duggan (Brian Lenihan 59), Daryl Horgan; Danny Morrissey, Stephen Kenny (Ian Turner h/t).
Referee: Rob Rogers (Dublin).
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