Armagh caused a massive shock as they defeated Down 0-14 to 1-10 in Sunday's Ulster Senior Hurling semi-final.
The Casement Park win earns Armagh their first Ulster Senior Hurling Final appearance since 1947.
Down had defeated Armagh by 17 points in a Christy Ring Cup game a number of weeks ago.
The Mourne County led 0-7 to 0-6 at half-time and Gareth Johnston then goaled for Down but a late Conor Corvan point helped Armagh take the victory.
Down defeated Armagh 4-24 to 0-9 in last year's Ulster Championships and were overwhelming favourites to qualify for a fifth straight Ulster decider but Armagh tore that script to shreds with a stunning finish.
Ryan Gaffney and former Down player Ruairi McGrattan led an Orchard County comeback with the latter claiming the equalising point, before Corvan's winner sent the Armagh support into raptures at the full-time whistle.
Derry defeated Armagh 1-14 to 1-8 in Sunday's Ulster Minor Hurling semi-final.