Tommy Lyons's first match at Parnell Park ended in defeat, as Louth came out 0-12 to 1-8 winners to progress to the semi-finals of the O'Byrne Cup.
Louth made the most of their few chances, with corner forward, JP Rooney, notching up three points and Mark Stanfield adding four points.
Dublin, on the other hand, wasted countless opportunities, and, during the course of the 70 minutes had 17 wides.
They started very brightly with Colin Moran and John McNally creating havoc in the Louth defence, though both players were guilty of missing easy opportunities and, at the break, Louth led by six points to five.
Dublin started the second half extremely brightly, with McNally grabbing two quick points, but Louth quickly regained their advantage, thanks to points from Christy Grimes, David Reilly, Mark Stanfield and SΘamus O'Hanlon.
Tommy Lyons made a spate of substitutions, and it looked like the game was slipping away from the Dubs, but with just minutes remaining, Moran jinked his way past five Louth defenders before crashing his shot past Colm Nally in the Louth goal to level the scores.
However, with almost the last kick of the game, Louth ensured victory when J P Rooney scored a brilliant point.
DUBLIN: S Cluxton; S Ryan, P Andrews, D Henry; B Cahill, M Breathnach, C Keane; K Darcy, C Murphy; E Crennan (0-1), J Madden, L ╙g ╙ hEineachain; C Moran (1-1), S Walsh, J McNally (0-5, three from frees). Subs: J Greene for E Crennan, D McGee for C Keane (both half-time); W Curtis (0-1) for J Greene (51 mins); K Devine for J Madden (55 mins).
LOUTH: C Nally, A McKenny, D Shevlin, D Brennan, S Gerard, C Quinn, J Neary, S O'Hanlon (0-1), M Farrelly (0-2), O Mc Donnell, K Lynch, M Stanfield (0-4, three from frees), D Reilly (0-1), C Kelly, JP Rooney (0-3). Subs: A Rogan for A McKenny (Half-time). C Grimes (0-1).