Monaghan Utd - 1 Dublin City - 0: A disciplined Monaghan United - inspired by midfielder Anto Murphy - made this a game to forget for struggling Premier Division side Dublin City, who had four men booked and one sent off on their way to crashing out of the FAI Cup at Century Homes Park.
Dublin City had the best of the early play, but they were exposed defensively in the 19th minute. Monaghan midfielder Jimmy Fulham crossed from the right and Anto Murphy escaped his marker to head into the top corner.
Monaghan should have been two up after 22 minutes, but Alan O'Connor blasted his shot wide when clean through on goal.
Dublin City's comeback hopes were dealt a severe blow in the 48th minute when striker Gary O'Neill was sent off for an ugly challenge on Murphy.
But Monaghan failed to exploit the numerical advantage, with Gavin Doyle and O'Connor both squandering close-range chances to seal the game. City mounted a late spell of pressure and in the 82nd minute it took an outstanding one-handed save from Monaghan goalkeeper Vladimir Munteanu to keep out Derek Griffin's long-range shot.
Monaghan had to survive seven minutes of added time before they could celebrate.
MONAGHAN UNITED: Munteanu; J Murphy, Jackson, Graham Doyle, Kelly, Fulham, Holt, A Murphy, Shiels, Gavin Doyle, O'Connor. Subs: Markey for Fulham (74 mins); O'Meara for A Murphy (77).
DUBLIN CITY: Kennedy; Burke, Griffin, Deans, Foy, O'Connor, Crowley, Colwell, McGill, Hughes, O'Neill. Subs: Brennan for O'Connor (45 mins); Collins for Burke (56); Scully for McGill (74).
Referee: D Hanney (Dublin).