Donegal set up an Ulster SFC semi-final against Tyrone as they outclassed a youthful but limited Cavan side.
Cavan's Ray Cullivan and Donegal's Michael Murphy both received straight red cards in the opening 13 minutes after a scrappy start at Breffni Park.
However, youngster Patrick McBrearty's goal steadied Donegal as they moved into a 1-6 to 0-3 lead by the break.
Rory Kavanagh's goal ended the game as a contest and Michael Brennan's late goal was little Cavan consolation.
Both teams made late changes to their starting line-up with Dermot Sheridan replacing James McEnroe in the Cavan defence and county minor McBrearty taking over from Kilcar club-mate Michael Hegarty in the Donegal attack.
McEnroe's absence reduced Cavan's list of Championship debutants to seven but it still looked a massive task for the Breffni County's under-21 dominated line-up.
The match started off with a distinct lack of atmosphere at Kingspan Breffni Park with the wet conditions clearly convincing many fans to give the occasion a miss.
The 9,325 people who did turn up were treated to a scrappy and laboured opening with Johnston and Murphy notching early frees at either end.
The temperature did unexpectedly rise in the seventh minute after Cullivan was handed his straight red by referee Marty Duffy for a crazy kung fu type kick on Kevin Cassidy, after the Cavan man had soared to win possession.
Initially, Donegal made nothing of their man-advantage as their early tactic of high balls into the Cavan defence floundered.
But it was 14 against 14 in the 13th minute after Murphy was harshly dismissed for a bit of shoulder to shoulder off the ball which left debutant Damien Reilly on the floor.
However, Murphy's departure galvanised Donegal with McFadden's levelling free then followed by McBrearty's 20th-minute goal.
McBrearty hammered to the net soccer-style after holding off Dane O'Dowd to win a line ball from Mark McHugh.
McDermott cut Donegal's lead to two ahead with a 24th-minute free but the visitors - helped by the introduction of Michael Hegarty - hit the last four scores of the half, including superb efforts from play from McFadden, Cassidy and McBrearty.
Six points in arrears, Cavan needed to make a fast start to the second half but Kevin Rafferty kicked over an immediate point and after Gearoid McKiernan's reply, another fine McFadden effort from play extended Donegal's lead to seven.
And any doubt about the outcome was ended when Kavanagh slammed in Donegal's second goal on 45 minutes with the Cavan defence marked absent.
With Donegal taking their foot off the pedal, the teams traded points in the closing stages with substitute Dermot Molloy accounting for three of the visitors' late scores.
Michael Brennan notched an injury-time goal for Cavan after Seanie Johnston's weak penalty had been saved by Paul Durcan.
Donegal had kept plenty in reserve but it was surely a satisfactory outcome for Jim McGuinness ahead of the semi-final clash against Tyrone in two weeks.
Cavan: J Reilly; J McEnroe, P Carroll, D O'Dowd; N Murray, J McCutcheon, D Reilly, R Cullivan, D Givney, G McKiernan, M Lyng, F Flanagan, N McDermott, E Keating, S Johnston.
Donegal: P Durcan, K Lacey, E McGee, P McGrath, M Boyle, A Thompson, K Cassidy, R Kavanagh, K Rafferty, M McElhinney, M Hegarty, R Bradley, C McFadden, M Murphy, M McHugh.
Sunday's Championship results
Leinster Football Championship
Carlow 0-14 0-13 Louth
Roscommon 2-12 0-6 Leitrim
Waterford 3-15 3-14 Limerick
Ulster SHC semi-final
Armagh 0-14 1-10 Down
Ulster MHC semi-final
Derry 1-14 1-8 Armagh