Derry City secured their place in the Semi Finals of the Setanta Sports Cup following a 1-0 win over St Patrick's Athletic at Richmond Park.
Kevin McHugh netted the all-important winner on 33 minutes following a period of sustained Candystripe pressure.
St Pat's must now beat Glentoran at The Oval in a fortnight's time and hope Derry beat Linfield on the same night to make it an all-League of Ireland Semi-Final line up.
In a sensational start, Pat's nearly took the lead inside 55 seconds when Gary Dempsey put Derek O'Brien through along the left wing. But having made a fine run on goal with just Derry goalkeeper Ger Doherty to beat, the former Galway United man scuffed his shot.
Sammy Morrow shot over for Derry on six minutes before Keith Fahey tested Doherty with a scorching shot from 25 yards on nine.
Pat's keeper Barry Ryan then came to his side's rescue on 16 minutes with a world class save from a superb Barry Molloy header after an inch-perfect Gareth McGlynn cross from deep on the right.
Kevin Deery struck a powerful free-kick for Derry on 22 minutes but it went agonisingly wide of the post while McGlynn shot over on 28 and Ryan denied McHugh on 32.
All that pressure paid off for Derry a minute after that when Ryan couldn't do anything to stop McHugh's drive through a congested goalmouth following good work from Steven Gray and Deery. It could have been two on 45 but Ryan did well to palm away a Morrow effort.
Pat's, who lost David Partridge to a shoulder injury in the first half, introduced Alan Kirby for Gary O'Neill for the second period. Kirby characteristically got stuck in immediately.
Slotting in just behind Ryan Guy and Mark Quigley, he went close himself on the hour mark with a shot from a tight angle that went over the bar at the Kilmainham end.
Apart from the creativity of Kirby and Fahey there was very little for the Pat's fans to cheer about and not a lot in the way of decent scoring chances.
Next up for Derry City is the Eircom League Cup Final against Wexford Youths on Saturday night whilst Pat's host Sporting Fingal in their FAI Ford Cup quarter final replay on Friday before facing Hertha BSC in the UEFA Cup at the RDS on Tuesday.