Galway, having lost their opening five games, came within inches of staving off the drop but in the end paid the price for their poor form early in the campaign.
Dublin will experience some of those shortcomings in the league final with Alan Brogan set to miss the date with Cork having been red-carded after seven minutes.
An off the ball incident involving Brogan and Galway defender Johnny Duane was spotted by linesman Vincent Neary and the Sligo official alerted referee Pat Fox to it at the next break in play.
Gilroy now prepares his team’s bid for their first league title since 1993 while Tomás Ó Flatharta will be knocking his side into shape for the championship against the backdrop of relegation.
Ó Flatharta said: “It was disappointing, we put in a great second-half performance.”
Dublin brought a lot of people back behind midfield in the second-half and they crowded that area. However I thought we got some excellent points in the second-half.”
The display of Gareth Bradshaw, introduced in the second-half, will have given the Galway faithful a lot of hope when others such as Michael Meehan and Sean Amrstrong return.
And while relegation is a big blow, the blooding of a lot of young players such as U21 captain Colin Forde at full-back, Johnny Duane at corner-back and Cathal Kenny at wing-forward is a boost, along with the positioning of Finian Hanley at midfield and another newcomer Greg Higgins at centre-back.
Dublin, with Paul Flynn working hard at wing-forward and Sean Murray and Denis Bastick effective in midfield, pulled ahead by 2-7 to 0-6 with the wind.
They got a glorious start when Flynn fed a low ball into Alan Brogan, who rounded Duane before goaling after less than three minutes. Brother Bernard — a third sibling Paul was at full-back — kicked four points in the opening half.
Galway paid the price for sloppy defending when Pat Burke was presented with a glorious opportunity which he did not spurn after 27 minutes to drill the ball low into the net.
Galway had reduced the deficit to a point at that stage but Dublin proceeded to score 1-4 without reply before Galway ended 18 scoreless minutes when Cormac Ban pointed.
Bradshaw and Conroy added another brace quickly as the Tribesmen hit 0-8 without reply, drawing level through sub Kevin Brady with seven minutes left. Dean Kelly kicked Dublin’s second score of the half with five minutes remaining but while Bane equalised in stoppage time Galway could not conjure a winner with a long range effort from Sice dropping inches short with the final kick of the game.
Scorers for Galway: P Joyce (0-4fs); C Bane (0-4, 2fs); P Conroy (0-3); E Concannon (0-1); G Sice (0-1); G Bradshaw (0-1); K Brady (0-1).
Scorers for Dublin: B Brogan (0-5, 4fs); A Brogan (1-0); P Burke (1-0); D Bastick (0-1sl); P Flynn (0-1); D Kelly (0-1); S Murray (0-1).
Subs for Galway: N Coyne for O’Donnell, (ht); G Bradshaw for Clancy, (42); K Brady for Kenny, (52).
Subs for Dublin: M Fitzsimons for Devereux, (ht); D Kelly for Burke, (54); D Lally for Connolly, (60); P Andrews for Cullen, (68); D Nelson for Kelly, (inj, 70).
Referee: Pat Fox (Westmeath).