Murphy’s sensational second half goal was the telling score of this game as Donegal continue to lookmore and more impressive under Jim McGuinness.
The most telling aspect for Donegal was how they kept their heads and fought back as Derry threatened to run away with the game in the early stages.
Keelan O’Boyle hit two goals on a rare start for Derry but Colm McFadden and Murphy cancelled out those strikes and Jim McGuinness’ side went on to claim the points by 2-18 to 2-12.
Derry were 1-11 to 1-09 behind at half-time despite a second minute goal from late call-up Caolan O’Boyle and a clutch of points from Conleith Gilligan.
O’Boyle scored a penalty to level the sides at 1-13 to 2-10, but Murphy, whose marker Kevin McCloy was sent-off, guided Donegal to victory.
Derry made the early breakthrough in this Division 2 tie, moving 1-01 to 0-00 ahead inside the opening two minutes.
Enda Muldoon knocked the ball down for O’Boyle, who was deputising for Paddy Bradley at full-forward, to score the first half.
The pair repeated the trick just moments later, only this time PJ McCloskey’s long delivery in was broken down by Muldoon for O’Boyle to rattle the back of the net.
A terrific individual score from Martin McElhinney got sluggish Donegal off the mark and they added a pointed free from Murphy, into a fresh wind.
Gilligan fired over a brace of frees, sandwiching a well-taken point from play from the visitors. Murphy won the ball and fed Colm McFadden who popped the ball over despite the presence of two defenders.
It was a free-scoring first half with some exciting passages of play when the pace quickened, and there were also three yellow cards awarded.
Derry maintained their one-goal lead thanks to points from Gilligan and Gerard O’Kane, in response to Dermot Molloy and Murphy.
Rory Kavanagh became the second Donegal midfield to score and McFadden’s second point whittled the gap down to the minimum – 1-05 to 0-07.
The movement of Murphy and McFadden was causing serious problems for the Derry defence, and the former raced through to slot home Donegal’s opening goal five minutes before the break.
Ryan Bradley’s ball in was missed by Ciaran Mullan and McFadden exposed some poor defending with a neat finish from near the end-line.
McFadden finished the half with 1-02 and with Molloy kicking four frees, Jim McGuinness’ side looked well set-up for the second half at 1-11 to 1-09 ahead.
Ciaran McGoldrick and substitute Charlie Kielt added their names to the Derry scoresheet before the interval.
Donegal lost the services of full-back Neil McGee through injury early in the second half, with Jason Noctor replacing him.
Donegal were 1-13 to 1-10 to the good 15 minutes into the second half following scores from McFadden and Murphy. O’Kane produced the Derry point.
Then came Derry’s penalty. Gilligan was fouled after he gathered a high ball and youngster O’Boyle took his tally to 2-01 with a superb strike. Donegal responded with a point from Molloy and a memorable solo goal from that man Murphy.
Murphy rose to gather a high ball above McCloy, turned past the defender and took a few strides before rasping an unstoppable shot to the left corner of the net.
Worse followed for McCloy when he picked up his second yellow card and received his marching orders.
Murphy and Muldoon traded points and Derry were still in the hunt with five minutes remaining, after Gilligan had pointed a free – his sixth of the night.
That made it 2-15 to 2-12, but there was no stopping Murphy, who kicked a late brace, and corner back Karl Lacey also showed his finishing skills as Donegal’s third win took them to the top of the table.