In a dress rehearsal for their championship meeting in June, Derry beat Donegal in Letterkenny to win through to their first NFL Division 1 final since 2000.
Derry will meet Kerry in the league decider and owe this win to a strong first half display which had them leading by 0-10 to 0-03 at half-time.
Michael Hegarty and Colm McFadden (0-02) were the hosts' only scorers during the opening 35 minutes.
And despite an improvement in the second half from Donegal, Derry kept ahead with Paddy Bradley claiming six points.
A 2,000-strong crowd watched on at the home ground of St. Eunan's as Derry got the win they required to keep their league run going.
Donegal were level with Derry on eight points in the table before the throw-in and Brian McIver's men were suitably pumped up as they chased a win that would keep their league title defence alive.
The visitors were forced into a late change with goalkeeper John Deighan crying off and Barry Gillis taking his place.
Derry were first out of the traps with Conleith Gilligan landing a free after only 30 seconds' play.
Michael Hegarty replied for Donegal from a placed ball, but efforts from Eoin Bradley (7 minutes) and strapping midfielder James Conway (13) had Derry 0-03 to 0-01 ahead.
Derry's early dominance stemmed from the back where Kevin McCloy was the outstanding player.
Colm McFadden notched his first point, from a free 22 metres out, but Donegal went scoreless for the next 15 minutes as their Ulster rivals foraged clear.
Gilligan hit a free, Fergal Doherty fisted the ball over the crossbar and Gilligan and Paddy Bradley added further points as the Oak Leafers pushed 0-07 to 0-02 ahead.
2007 All-Star Bradley took control as he hit the half's closing three points with McFadden (free) grabbing Donegal's only response.
The Tir Chonaill men could have had a goal close to half-time but Leon Thompson's effort was scrambled away from the target.
Donegal, who turned around with the wind at their backs, made a business-like start to the second half with Thompson and McFadden raising white flags.
But Mark Lynch and Bradley quickly responded and Derry remained firmly in control, leading by 0-12 to 0-05 with 43 minutes on the clock.
Donegal did kick four of the next five points as McFadden (0-02f), Frank McGlynn and Christy Toye helped themselves to scores, with Bradley the man to take Derry's tally to 0-13.
Derry waivered slightly as Gilligan missed a simple free and they lost defender Kevin McGuckin to a second booking.
But points from Michael McIver, the son of Donegal manager Brian, and Enda Muldoon saw Derry keep their foot on the gas.
Donegal's Michael Doherty did have a late chance with an injury-time penalty but, with time not on the hosts' side, he planted it over the bar as Derry were too far in front.