Louth recovered from four down at half-time to beat Antrim 3-12 to 1-14 in the Football League Division Four final.
Derek Maguire's goal helped Louth lead but Matthew Fitzpatrick's 30th-minute strike put the Saffrons three up and they led 1-9 to 1-5 at the break.
Antrim extended their advantage to five but Jim McEneaney netted for Louth as they responded with 1-4 to lead.
A Tomas McCann free levelled the game on 69 but Conor Grimes' injury-time goal sealed Louth's deserved win.
Antrim appeared to settle the better as scores from McCann and Brian Neeson gave them an early two-point lead.
But the Saffrons were stunned by Maguire's fifth-minute goal and Louth were still 1-3 to 0-4 ahead by the 22nd minute.
However, Antrim produced a strong finish to the second half to outscore Louth 1-5 to 0-2 helped by Fitzpatrick's 30th-minute goal after good work by McCann.
Another McCann score increased Antrim's lead to five after the resumption but Louth then began to take control as a succession of high balls caused consternation in the Saffrons full-back line.
After two James Califf frees were followed by a goalbound Declan Byrne's shot being deflected over for a point, Louth were suddenly ahead as McEneaney finished off a brilliant move.
A Ryan Burns score doubled Louth's lead by the 59th minute but Antrim ended a 20-minute scoring drought as Paddy McBride and Ryan Murray points levelled the contest again.
Extra-time looked on the cards as Burns and McCann kicked long-range frees at either end but Louth were able to burst their way through the porous Antrim defence in the first minute of injury-time as Grimes fired past Chris Kerr.
As Antrim desperately chased an equalising goal, a Kevin Niblock shot was blocked before Ryan Murray over-hit his attempted lob into the square and Derek Maguire's point at the other end was the insurance score.