Bluebell United v Shamrock Rovers, Tallaght Stadium, 7.45pm
Leinster Senior League outfit Bluebell United continue their fairytale run in the cup at Tallaght Stadium tonight, having ceded home advantage for their clash with the Dublin heavyweights.
Not since the great St Francis team in 1990 has a non-league side reached the last four of this competition, and Andy Noonan's men will be going all out to upset the odds.
Rovers have endured a 30-year wait for the FAI Cup. They've already secured a spot in the EA Sports Cup decider against Dundalk, and will be confident of seeing off the underdogs tonight.
Bluebell United: The Bell are without former Republic of Ireland international Keith Fahey who was sent off against Cabinteely and is suspended.
Shamrock Rovers: Ronan Finn is suspended, Graham Burke is out, while Sean Boyd will miss the rest of the season due to a stomach injury.
Stephen Bradley (Shamrock Rovers): "They’ve got some really good players and I know it’s going to be a tough game. If we were to think anything otherwise we’d be very foolish because they’re a good side. We’ve got to respect what they’re going to bring, their energy and passion."
Galway United v Limerick FC, Eamonn Deacy Park, 7.45pm
Galway United are looking to make the semi-finals for the first time in nine years.
They've overcome eliminate Dublin sides Killester United and St Patrick's Athletic to get this far, while Limerick have knocked out Cobh Ramblers and fellow Premier Division side Finn Harps.
The teams have already met on two occasions this season, drawing 1-1 at the Markets Field and the Tribesmen winning 3-1 at Eamonn Deacy Park.
Limerick edged out Finn Harps 1-0 in the last round and have yet to concede a goal in the competition.
Galway United: There are doubts over Rory Hale (back), Eoin McCormack (knee) and Niall Maher (hamstring).
Limerick: The Blues are at full strength for the trip to Galway.
Shane Keegan (Galway United): "I think it's a game where both teams are happy with the draw, both teams will fancy their chances. We have already beaten Limerick at Eamonn Deacy Park this season, that will give us confidence."
Dundalk v Drogheda United, Oriel Park, 7.45pm
Drogheda will look to salvage a challenging campaign in the top flight by pulling off a shock win against their neighbours.
Pete Mahon's Drogs are bottom of the Airtricity league Premier Division and look destined for the drop, but a win at Oriel Park would go some way to salvaging the season.
The Lilywhites are in flying form and will be strong favourites. They're also on a mission to exorcise the demons of last year's agonising loss to Cork City in the final.
Dundalk: Stephen O'Donnell, Dane Massey and John Mountney are all out through injury. Jamie McGrath is bakc in contention after his appendicitis.
Drogheda United: The visitors are missing Colm Deasy, Ciaran McGuigan, Kevin Farragher and Gavin Brennan while Chris Mulhall is suspended.
Stephen Kenny (Dundalk): "There's a derby element to it. In the cup you always expect a tough game. They are always difficult and we are at the quarter-final stage so this will be no different. The players are in good form though and we are scoring a lot of goals."
Pete Mahon (Drogheda United): "I think they're playing the best football in the country at the moment. It's the draw that everyone wanted to avoid but here we are and I've seen enough in football to know that anything can happen in a derby game."
Longford Town v Cork City, City Calling Stadium, 7.30pm
Former Cork City star Neale Fenn will be hoping to put one over his old side when the Rebels come to town tomorrow.
Since Fenn took over at the helm of Longford Town in June, he has guided the Midlanders to fourth place in the First Division.
En-route to Saturday’s last-eight tie, the Town have beaten Sligo Rovers and Leinster Senior League side Bangor Celtic. Their last league outing produced a 2-0 victory away to Cabinteely.
Cork are 14 points clear at the top of the Premier Division but have struggled in the league since the departures of Seanie Maguire and Kevin O’Connor, losing to Bohs, Sligo Rovers, and last time out to Shamrock Rovers.
However, the champions-in-waiting and reigning cup holders reached the quarter-finals with an impressive 7-0 thrashing of Athlone Town in the last 16 and a one-nil away victory over Bray in the first round.
Longford Town: Kevin O’Connor, Paul Skinner and Alan Kehoe are all injured.
Cork City: Johnny Dunleavy and Alec Byrne are long-term absentees, while Sean O’Mahony has also been ruled out. Alan Bennett and Garry Buckley are carrying knocks and will be assessed prior to the game.
Cork City (John Caulfield): "Since Neale Fenn has gone in, he has revitalised Longford and put his own stamp on the team. They have a lot of Premier Division experience and some very good players, so we are under no illusions that we will have to be at our best to get a result."