Strong recent history adds to anticipation
Tomorrow night's encounter in Navan will see Dublin and Longford clash for the third successive year at this grade with both counties having enjoyed one victory and endured one defeat.
Two years ago, a hotly fancied Dublin team were bundled out of the championship as Robbie Smyth's superbly taken goal proved pivotal as Longford pipped the Dubs by 1-6 to 1-5 at a rain-swept Parnell Park.
Ciarán Kilkenny's first-half goal handed Dublin a flattering interval lead but Longford were far more fluent in the treacherous conditions and regained the initiative in the second-half with Smyth to the fore.
Substitute Gavin Ivory offered Dublin hope with two excellent late points but despite the sending-off of captain Padraig McCormack in the 58th minute, Longford clung on for a well-deserved victory with Kilkenny missing a tricky free in injury time to force extra-time.
Twelve months later, Dublin gained a modicum of revenge with Paul Mannion's two early goals laying the platform for a relatively comfortable 3-7 to 0-6 win in O'Moore Park, Portlaoise.
Mannion struck for the first of his two goals after four minutes as Dessie Farrell's side opened up a commanding 2-2 to 0-0 lead inside 12 minutes, highlighting the potency inherent in the Dublin attack.
Longford laboured hard in the second half with Smyth landing four frees over the hour but the Dublin defence remained resolute with David Byrne and Stephen Cunningham providing a solid spine throughout while Eric Lowndes was hugely influential for Dublin.
The Dubs kept their noses in front with Cormac Costello landing three points from play and with four minutes remaining Dublin added a third goal when substitute Emmet Ó Conghaile fired to the net at the end of a move initiated by the tireless Lowndes.
2013 Leinster U21 FC quarter-final
Scorers - Longford: R Smyth 1-3 (0-1f), R O'Connor, M Hughes (f), D Cooney 0-1 each. Dublin: C Kilkenny 1-1 (0-1f), G Ivory 0-2, E Ó Conghaile, S Carthy ('45') 0-1 each.
2014 Leinster U21 FC semi-final
SCORERS - Dublin: P Mannion 2-1, C Costello 0-4 (1f), E Ó Conghaile 1-0, E Lowndes, C McHugh 0-1 each. Longford: R Smyth 0-4 (4f), B McKeon, P Kiernan 0-1 each.