Dublin 1-28 Galway 1-19
David Treacy did the damage for Dublin with 12 impressive points at Parnell Park to seal a Bord na Mona Walsh Cup hurling final spot at Croke Park next weekend.
Ger Cunningham's side advanced to a decider date with Wexford with surprising ease and had a talisman in Cuala's Treacy.
Aside from his excellence from frees and '65s', the county medallist also delivered one sumptuous point from a side line cut as the Dubs knocked out the tournament holders.
Apart from Treacy, sub Eamonn Dillon sniped 1-03, while Niall McMorrow and David O'Callaghan weighed in with seven points between them, pushing forward their respective cases for Allianz league starts next month.
Familiarity between these two teams last year clearly bred contempt as tensions boiled over when they met in November in the novel Fenway Classic Super 11s encounter in Boston.
Crucially, Galway came out on top in that contest, their third win in five meetings between the counties across four different competitions in 2015.
One of those Galway wins was February's Walsh Cup final though Dublin hinted early on here that they were ready to settle that old score at least.
The hosts led by 0-5 to 0-0 with 10 minutes on the clock and looked comfortable and composed.
McMorrow fired two over followed by efforts from the Treacy brothers, David and Sean, and one from Chris Bennett.
Dublin maintained a healthy four-point advantage with half an hour on the clock and looked threatening each time they probed forward.
But a bizarre 32nd-minute Galway goal ultimately sent the sides in level at half-time, 1-09 to 0-12.
Galway midfielder David Burke claimed the goal but Dublin 'keeper Conor Dooley was at fault for fumbling Burke's harmless effort onto his own post and over the goal line.
Galway, who topped Group 4 in the round-robin stage, had to start without key duo Colm Callanan and Joe Canning, who were late withdrawals.
Captain Liam Rushe was among five similar late withdrawals from the Dublin team with Fionn O Riain Broinn, Daire Plunkett, the Treacys and O'Callaghan coming in.
In Canning's place, Shane Moloney started for Galway and the youngster, who hit the winning point against Tipperary in last year's All-Ireland semi-final on his debut, converted three first-half frees.
The sides were level twice more early in the second-half before Dublin pulled decisively clear, blasting 1-02 without reply to nudge five clear again.
Dillon raised the green flag with a rasping ground stroke from around 13 metres out through a group of bodies.
Dublin maintained a comfortable advantage all the way from there and forged eight clear at one stage.
David Treacy continued to pick off the points from placed balls while O'Callaghan fired over two spectacular long range scores.
Dublin: C Dooley; J Boland, O Gough, S Durkin; B Quinn, C Crummey, J McCaffrey; N McMorrow (0-04), F O Riain Broinn; D Plunkett (0-01), F McGibb, D Treacy (0-12, 0-06f, 0-02 65, 0-01 s/l); S Treacy (0-01), D O'Callaghan (0-03), C Bennett (0-01).
Subs: E Dillon (1-03) for Crummey, P Ryan (0-02, 0-01f) for Bennett, S O'Reilly (0-01) for S Treacy, R Hardy for Durkin.
Galway: J Skehill; J Coen, R Burke, P Hoban; Daithi Burke, G Lally, P Claffey; David Burke (1-03), P Brehony; A Smith (0-02, 0-01f), G McInerney (0-01), N Burke (0-03); E Burke (0-02), S Moloney (0-05, 0-04f), D Glennon (0-02).
Subs: A Harte for Brehony, J Flynn (0-01) for Brehony, I Tannian for Lally, S Morrissey for Daithi Burke.
Referee: P O'Dwyer (Carlow).
