Kilkenny handed Dublin a bruising 13-point defeat at Parnell Park to put The Cats into pole position for a league semi-final spot.
Walter Walsh and Martin Keoghan scored the goals as the visitors led all the way from the third minute, with ten players registering scores for Brian Cody's side.
For Mattie Kenny and Dublin, the heavy loss ended a seven-game unbeaten run since the start of the Walsh Cup, though they can still make the Allianz Hurling League knockout phase.
Rian McBride hit the game’s opening score for the hosts but Kilkenny largely dominated the first half.
Midfielder Alan Murphy did the bulk of the damage with four frees and another from play.
Keoghan was giving Andrew Murphy plenty of trouble at the edge of the square and could have goaled after just three minutes.
A Billy Ryan pointed attempt came down off the post in front of the six-yard box, but Dunphy got his body in the way in the nick of time.
The Dubs had faded badly in their one-point win over Tipperary last week, narrowly escaping with the points as the Premier dominated the final minutes — hitting 13 of the final 14 shots.
Wastefulness was the issue this time as Dublin missed seven out of their eight scoring attempts between minutes two and 27, with Ronan Hayes and Donal Burke points providing some solace.
Cody’s men were full value for their half-time lead though as Wally Walsh (0-02), David Blanchfield and Keoghan found the range heading towards the interval.
Dublin needed a quick response to get back into the game, and they seemed to have found just that when stroking over three quick points through Hayes and Burke ('65 and a free).
The revival was short-lived however as the Cats blasted an unanswered 2-03 in a devastating ten-minute spell.
After Kilkenny had twice been denied by good Dubs defending, Keoghan snapped a breaking ball around the ‘21 and fed Wally Walsh to blast home from 14 yards on 44 minutes.
Padraig and Wally Walsh added further points before John Donnelly’s incisive break set up the second goal.
The Thomastown man broke onto a puckout, scythed down the middle of the Dublin ‘D’, before feeding Keoghan to finish low to the net.
Kilkenny continued to dominate the ground and aerial exchanges as Padraig Walsh took his tally to four points, Blanchfield went on to accrue 0-3, with Cillian Buckley and Mikey Carey (0-2) also on the board.
With 2-12 in the second half — all from play — Cody’s side collected a third league win of the season as the hosts suffered a chastening defeat in front of their home supporters.
Dublin: Alan Nolan; Andrew Dunphy, Cian O’Callaghan, John Bellew; Sean Moran, Paddy Smyth, James Madden; Chris Crummey, Conor Burke; Donal Burke (0-09; 6f, 1 ‘65), Riain McBride (0-01), Danny Sutcliffe (0-03); Fergal Whitely, Ronan Hayes (0-02), Aidan Mellett
Subs: Eamon Dillon for Whitely (46); Jake Malone for C Burke (51); Donnacha Ryan for Moran (52); Paul Crummey (0-01) for Hayes (58); Colin Currie for Mellett (61)
Kilkenny: Eoin Murphy; Mikey Butler, Huw Lawlor, Tommy Walsh; Mikey Carey (0-02), Paddy Deegan, David Blanchfield (0-03); Cian Kenny (0-01), Alan Murphy (0-05; 0-4f); Wally Walsh (1-03), Padraig Walsh (0-04), Tom Phelan; Cillian Buckley (0-01), Billy Ryan (0-02), Martin Keoghan (1-01)
Subs: John Donnelly (0-01) for Phelan (36); James Maher for Kenny (45);
Referee: Paud O’Dwyer (Carlow)
