Up to that Fermanagh looked as if they would cruise to victory as Peter Canavan's side built on a good finish to the first half that saw them go in three ahead at the break to move six clear by the 47th minute.
However, life was breathed into the Cavan challenge when Gearoid McKiernan tucked the ball into the corner of Ronan Gallagher's net in the 46th minute and when Niall McDermott replicated McKiernan two minutes later, Cavan suddenly found themselves a point to the good.
And from this to the end the Breffnimen dominated as the Fermanagh challenge disintegrated.
When Eugene Keating fired home a third Cavan goal was ten minutes to go there was no way back for Fermanagh as Cavan eased their way into the next round of the qualifiers.
It was the away side who started the game brighter with Keating proving a handful at full forward.
Jack Brady and Niall McDermott had opened the scoring before Daniel Kille opened the Fermanagh account from a free.
Keating had a good goal chance when he got on the end of a long ball but he fired wide although he did knock over a point soon after and when Niall Smith chipped in with an point it left Cavan with a three point advantage with 15 minutes gone.
Fermanagh though finally settled into the game after that with Shane McCabe a lively presence in the attack and Tomas Corrigan and Paul Ward closed the gap back to one.
McDermott tagged on another point for Cavan but Fermanagh were to account for the final five points of the half to give them the lead at half time.
Kille clipped over a free before Corrigan landed a good point from play to level matters.
And Canavan's side pushed on in the latter stages of the half with Kille kicking two points, one from a free, one from play, and Ward converted a free to leave it 0-08 to 0-05 at the break.
Cavan clipped over the first point of the second half with Jack Brady the scorer but Fermanagh soon regained the initiative as Kille slotted over two frees and Ryan Jones a point from play.
Brady did knock over a point from a free but Fermanagh responded with Kille and Corrigan lobbing over points to make it 0-13 to 0-07 with 12 minutes of the second half played.
The wheels were to come off the Fermanagh wagon though in the next spell as Cavan blasted their way back into contention.
Brady clipped over a free and then McKiernan bagged Cavan's first goal after Tommy McElroy had coughed up possession.
And Fermanagh were still recovering from that when McKiernan, who was a very influential figure in the second half, put McDermott in on and goal and he tucked his shot into the corner.
Cavan's tails were up and from this point there was no way back for Fermanagh as Damian Reilly and Thomas Corr clipped over points to make it 2-10 to 0-13.
Indeed, substitute Kevin Tierney had a goal chance but it was saved by Gallagher as Fermanagh's game evaporated.
Kille, who finished the game with a personal tally of nine points, slotted over to bring it back to a two point game but Cavan hit back with their third goal which finished off any notion Fermanagh had of winning the game.
The sides shared the last four points of the game but Cavan were never in any danger as they booked their place in the draw for round two.
R. Gallagher; J. Woods, B. Owens, B. Cox; C. Quigley, N. McGovern, B. Mulrone; S. Lyons, E. Donnelly; T. McElroy, P. Ward (0-2, 1f), R. Jones (0-01); T. Corrigan (0-03), D. Kille (0-09, 8f), S. McCabe.
Subs - D. McCusker for McElroy, M. McGrath for Cox, S. Quigley for Ward, M. Jones for C. Quigley, P. Cosgrove for Mulrone.
J. Reilly; K. Clarke, P. O'Reilly, D. Tighe; M. McKeever, D. Reilly (0-01), F. Flanagan; D. Givney, T. Corr (0-01); N. Smith (0-01), G. McKiernan (1-01), R. Flanagan; N. McDermott (1-02), E. Keating (1-01), J. Brady (0-04, 2f).
Subs - K. Tierney (0-01) for Givney, J. McLoughlin for Clarke, D. McKiernan (0-01) for M. McKeever, K. Meehan for Smith.