An understrength Donegal were no match for a Cork side who were in greater need of the points at a wet Pairc Ui Rinn.
Donegal without the inspirational Geraldine McLaughlin as well as the Hegartys, were just a pale shadow of the team that was unbeaten to this stage.
The lack of firepower with the absence of McLaughlin and Hegarty was noticeable for Donegal in the opening half. They had plenty of possession and won 19 first half frees to Cork's 10, but the game was as good as over at the break.
Cork were 0-8 to 0-1 up and their forwards were making use of the ball. They were almost in for a goal in the fifth minute when Eimear Scally broke through but her shot was very well saved by Aoife McColgan in the Donegal goal.
Orlagh Farmar and Niamh Cotter had Cork on the board by the eighth minute before Donegal got their only point of the half in the 10th minute, Katy Herron winning a free on a good run and Karen Guthrie converting.
Herron and Guthrie, along with Roisin Friel, did have chances in the opening half, but they were off target or their shots fell short.
Cork kept the scoreboard ticking with points from the excellent Orla Finn (3) from frees and one from play (though she was lucky to get away with two hops). Orlagh Farmer and Aine O'Sullivan also chipped in with points as the rain came down on Pairc Ui Rinn.
It got worse for Donegal within minutes of the restart as Eimear KIely had a point. Orla Finn hit the crossbar with a free but on four minutes Ashling Hutchings cut through to fire to the Donegal net.
Dara Kiely added a point, Finn added two frees and Melissa Duggan had it 1-13 to 0-1 after 42 minutes.
Donegal did get a point on the board when Karen Guthrie pointed a free but Cork replied through Ciara O'Sullivan.
It was to get worse for Donegal as after a slick move Niamh Cotter had the easy task of firing home the second goal on 49 minutes.
Karen Guthrie got Donegal's third point, also a free, as Ciara O'Sullivan rattled over a brace at the other end with the game out of sight.
Karen Guthrie got a late free but Cork replied again, this time Ciara O'Sullivan getting in for a third goal to add salt to the Donegal wounds.
Scorers - Cork: Orla Finn 0-6,4f; Niamh Cotter 1-1; Ciara O'Sullivan 1-3; Ashling Hutchings 1-0; Orlagh Farmer 0-2; Daire Kiely, Melissa Duggan, Eimear Kiely, Aine O'Sullivan 0-1 each
Donegal: Karen Guthrie 0-4,3f.
CORK: Martina O'Brien; Shauna Kelly, Hannah Looney, Maire O'Callaghan; Daire Kiely, Melissa Duggan, Eimear Kiely; Ashling Hutchings, Ciara O'Sullivan; Aine O'Sullivan, Niamh Cotter, Orlagh Farmer; Eimear Scally, Libby Coppinger, Orla Finn.
Subs: Eimear Meaney for S Kelly 36; Laura O'Mahony for A O'Sullivan 38; Doireann O'Sullivan for Finn and Rhona Ni Bhuachalla for Coppinter 43; Laura Cleary for Cotter; Emma Spillane for E Kiely, Ciara O'Shea for Hutchings, Meabh Cahillane for D Kiely all 50.
DONEGAL: Aoife McColgan; Anna Marie McGlynn, Emer Gallagher, Evelyn McGinley; Treasa Doherty, Nicole McLaughlin, Niamh Carr; Katy Herron, Niamh Boyle; Karen Guthrie, Shannon McLaughlin, Amy Boyle Carr; Shannon McGroddy, Megan Ryan, Roisin Friel.
Subs: Anna Flanagan for R Friel ht; Julie Trearty for S McLaughlin 45; Sinead McGinty for A McGlynn 48; Elaine Melaugh for McGroddy 50; Kanesha McKinney for E Gallagher, Lauren Carr for Ryan both 54; Ashling Nee for A Boyle Carr 59
REFEREE: Shane Curley (Galway)