GOBSMACKED might be how Down feel after losing this tight, tense tussle and they can certainly feel that a disputed smack to a mouth cost them dearly.
Conall McGoverns alleged indiscipline at the very start of the second half left the Mournemen a player short for almost that entire period, the Burren clubman receiving a straight red card for striking Enda Lynn off the ball from the throw-in but it was a harsh decision.
Derry looked like cruising to a comfortable victory after that, opening up a four-point lead, 10-6 with half and hour to play - but they then retreated into a defensive shell and Down almost left them shell-shocked with a spirited comeback.
The red-and-blacks drew level within 15 minutes, inspired by their captain Conor Laverty, who was tremendous in the second half, the little man pulling the strings from a deeper position.
However, having worked so hard to achieve parity, Down could not get their noses in front, which might have turned their hosts mental wobble into a complete collapse.
Paul Devlin wasted one opportunity, substitute Jerome Johnston another with a wild effort, and Derry finally showed some composure and vigour to force the winning score in injury time.
Eoin Bradley ran at the heart of the Down defence and hand-passed to the overlapping wing-back Kevin Johnston, who was hauled down by Darren OHagan. That earned the Clonduff clubman a black card, but the real damage was done as it left Skinner Bradley with a simple free to separate the sides.
Devlins free-taking had seemed set to earn the visitors at least a replay yet it was Downs inaccuracy and that earlier indiscipline - which cost them in the end. The Mournemen registered 12 wides, 10 of them very scoreable, including two frees from Devlin.
Derry did miss four frees themselves in their tally of seven wides, and should probably have converted two of the other three chances, but Down were more profligate.
Having said all that, Down only led once during the entire match, and that was the opening score, a Donal OHare free. That proved to be his only score of the match as he was well-watched by Derry vice-captain Dermot McBride.
Indeed the only Down attackers to score from play were Laverty and Kevin McKernan, the latter involved in a running battle of the right kind with his namesake Johnston.
As anticipated, this game was nip and tuck almost throughout, with both sides setting up in similar style by using sweepers.
Derrys tackling was impressive in that first period, whereas Down made more fouls, troubled by Lynns running in particular, and the sheer strength on the ball of Bradley.
The recalled Ryan Boyle was soon moved off Lynn, switching to the sweeper role with McGovern taking over that man-marking duty.
At the other end, Downs small, quick attackers were struggling to break through the defensive screen, and even when Mark Poland did so he was well-tackled by Ciaran McFaul.
Laverty then picked out Peter Fitzpatrick with a pass over the top but the big midfielder blazed his shot wide when he might even have hit the net, and OHare also missed a chance.
Derry took advantage on the scoreboard with a powerful conclusion to the first period, veteran midfielder Fergal Doherty literally rising to the occasion. The Bellaghy man took two high catches that led to scores, both swung over the bar by skipper Mark Lynch.
That opened up the games biggest gap, three points, at 0-8 to 0-5, and although Laverty fisted a point inside 20 seconds of the re-start, the sending-off of McGovern, which followed consultation between the officials, appeared to swing the game firmly in Derrys favour.
The Oak Leafers did double their advantage within four minutes, from a Lynch free - after yet another foul on Lynn and a fine score by Bradley, but they failed badly to build on that.
Indeed Derry went 21 minutes without scoring, during which Down were dominant, boosted by the introduction of Packie Downey and moving Laverty further out the field.
Downs darts at the packed Derry defence kept drawing fouls and Devlin kept converting the subsequent frees.
Their equalising score was a beauty, fittingly scored by Laverty, off his right foot from way out on the right wing.
The game was bubbling up as the temperatures rose and a scuffle broke out, starting with Mooney and his marker Niall Holly, leading to bookings for those two and also Poland and Daniel Heavron.
Derry seemed to belatedly realise that they might actually lose, never mind not win, and went ahead again in the 62nd minute, albeit slightly fortuitously. Dungiven man Johnston miscued a shot but substitute Cailean OBoyle leapt highest to fist the ball over the bar.
Still Down came at them and Devlin converted another free, but then he and his Kilcoo clubmate Jerome Johnston could not take their chances.
The Down management were more ruthless than their forwards, taking off both Mooney and Devlin after they botched openings, the former messing up a hand-pass when running through. Yet their replacements could not force a lead score.
Derry won it with an assist from their goalkeeper Thomas Mallon, whose precise kick-outs were a feature of this match, notably to Doherty around centre-field.
This time, though, the Loup man guided the ball out to the right wing, right to Bradley, who then arrowed in towards goal before releasing Johnston. OHagan could not gamble on him missing from close range and pulled him down but Bradley was never going to miss the free either.
Skinners score brought Derry their first Ulster SFC victory over Down in 22 years albeit at only the third attempt and their first home win in the provincial championship in four years after defeats in the past two seasons by Donegal and the Mournemen.
Yet Derry will have to be much better, and much more ambitious, against either Armagh or Donegal, who meet at the Athletic Grounds next Sunday for the last semi-final place.
Star Man: Thomas Mallon
Like a lot of Derrys scores, the match-winning score originated with a kick-out from Thomas Mallon.
The Loup clubman had a fantastic game. For the last point of the match, he spotted Eoin Bradleys run to the wing and Mallon picked him out with razor-sharp kick-out.
Over the course of the match, Mallon enjoyed a 75 per cent success rate with his kick-outs.
Given that the Derry goalkeeper rarely went short, and that he was placing his efforts to the midfield sector, his re-starts were incredibly accurate.
Derry Match Ratings:
Oisin Duffy: Had a tough tussle against Conor Laverty, who kicked two points. Duffy stuck to his task. Unlike some of his colleagues, he didnt concede any cheap frees. 6.5
Brendan Rogers: Guilty of conceding two scoreable frees, both for fouls on Mark Poland. Otherwise the young Slaughtneil man made a fantastic debut. Impressed with his willingness to attack the ball and win the ball in front of his man. Composed, strong and very athletic. 6.5
Dermot McBride: Held Donal OHare scoreless although he coughed up one free, which was converted. Made a vital play in the 60th minute when he intercepted a Caolan Mooney pass to OHare. 7
Kevin Johnston: His duel with Kevin McKernan was an engrossing affair. McKernan landed two exceptional points. But Johnston caused plenty of damage with his counter-attacks. Was fouled for the match-winning point. 7.5
Christopher McKaigue: Marked Conor Maginn and kept a tight rein on the Bryansford man. Made a couple of forward bursts but never got into a scoring position. 6.5
Ciaran McFaul: Picked up Paul Devlin and was never exposed. Made a superb tackle in the first half when he dispossessed Poland as he charged through on goal. Was disciplined in his tackling. 7
Fergal Doherty: Performed the role of midfield anchorman. Operated mostly between the two 45s. Was there to claim primary possession and performed his role with aplomb, winning eight clean catches over the course of the game. Lost Fitzpatrick when he could have bagged a goal. 7
Sean Leo McGoldrick: Registered a trademark display in the first half when he popped up everywhere. Was less prominent in the second half. 6
Mark Lynch: Put Derry in the driving seat when he landed three excellent points during the last five minutes of the first half. Was pushed into the full-forward line for much of the second half and was starved of possession. 7.5
Enda Lynn: Caused Down a lot of headaches in the first quarter. Clipped a fine point and was unlucky not to earn a penalty. Drew two scoreable frees and both were converted. 7
Benny Heron: Appeared to be fouled when trying to engineer a shot on goal in the first half. Acted as an outlet player and worked back to help the defence. 6
Eoin Bradley: Deserves huge credit for presenting himself and winning the kick-out which led to the winning score. Bradley effectively won the game for Derry with that catch and run. Despite being double-teamed he landed to extraordinary points. 7.5
Danny Heavron: Played sweeper from start to finish. Made himself available for short kick-outs. Composed in possession and distribution was solid. 6.5
Substitutes
Caolan OBoyle: Under-utilized. Showed his threat when he collected a long ball from McFaul. It was the only pass he received. Used his long reach to good effect when he fisted a looping ball over the bar. 6
Terence OBrien: Unfairly punished for over-carrying after he showed courage to win a kick-out. Lost possession with a bad pass when he had other options. 6
Down Match Ratings:
Stephen Kane: Poor early kick-out, but directed others well enough to runners out wide. Didnt have a serious save to make. 6.5
Darren OHagan: Up against Eoin Bradley and stuck to his task admirably, although his opponent was in fine form and hard to shake off the ball. 6.5
Luke Howard: Generally got the better of Benny Heron, although he was booked after the referees attention was drawn to an off-the-ball incident. Troubled more by Cailean OBoyles height. 7
Ryan Boyle: Pitted against the pacy Enda Lynn at first but soon moved to the sweeper role. Attacked well and kept Lynn quiet when back against him after the red card. 7
Damian Turley: Marking Sean Leo McGoldrick and was able to attack quite well, although hit a late wide before the break. 6.5
Brendan McArdle: Put Mark Lynch on the back foot at times but could not curtail him for a short spell before the break when he kicked three points from play. Did better on him when he went up to the square. 6.5
Conall McGovern: Started as sweeper and made one easy interception but inside 15 minutes was moved to mark Lynn and curtailed him somewhat. Sent off after an umpire reported to him to the ref for striking Lynn. 5.5
Peter Fitzpatrick: Began the match strongly, getting forward, but kicked two wides, one of them terrible, and Fergal Doherty dominated shortly before the break. Continued to attack but was out-fielded by his opponent. 6.5
Caolan Mooney: Tried hard to get going in this game but never really escaped the attentions of Niall Holly, who was happy to follow him to the square. 6
Paul Devlin: On the right wing, found it hard to get away from McFaul, although he kicked a couple of wides. Was more accurate with his frees, kicking six out of eight. 6.5
Conor Maginn: Flitted in and out, assisting McKernans second score with a rapid hand-pass and kicked some smart passes too. Replaced by Downey in the 48th minute. 6.5
Kevin McKernan: Had a great battle with Johnston, who was pushing up throughout the match. The Burren man won ball and kicked two good first half points but his opponent was influential late on. 7.5
Mark Poland: One sight of goal snuffed out by a tough tackle from McFaul. Kept showing for the ball and suffered a few fouls. Dropped one short poorly short. 6.5
Conor Laverty: The captain had a quiet first half, although he picked out a great pass to Fitzpatrick. Really came alive after the break, scoring two points and making things happen from a deeper role. 7.5
Donal OHare: Opened the scoring but that was that in that regard. Kicked one wide after a clever run. Worked hard in the second half, including robbing Rogers of the ball. 6
Substitutes:
Packie Downey: Replaced Maginn with a third of the game to go and made a good impression with his passing, although he shot one long range effort wide. 7
Jerome Johnston: Came on for Fitzpatrick in an attacking change but shot one silly wide. 6
Arthur McConville: Not on long enough to be rated.
Niall Madine: Not on long enough to be rated.
Darragh OHanlon: Not on long enough to be rated.
TACTICAL TAKE Derry
Somewhat surprisingly, Ciaran McFaul did operate in defence, marking Paul Devlin, and did that well, also dispossessing Mark Poland impressively. As expected, Daniel Heavron was back as sweeper, but he did not bring the ball out from the back.
Goalkeeper Thomas Mallon and big midfielder Fergal Doherty had clearly worked hard on kick-out strategy, which paid dividends, including for the winning score.
Mark Lynch was pushed further up in attack at the start of the second half but Derry failed to find him very often, with long kicks or by working the ball up to him.
They also did not sufficiently exploit having an extra man for almost an entire half.
TACTICAL TAKE Down
Derrys withdrawal of their number 15, Heavron, as sweeper allowed Down to deploy a spare defender, first Conall McGovern then Ryan Boyle. They boldly dispensed with that in the second period after McGovern was sent off.
Jim McCorry also cleverly brought Conor Laverty much deeper, having had little joy at full-forward, and the captain began to pick out passes and score himself.
Down moved Caolan Mooney up and down between midfield and full-forward but his marker Niall Holly is comfortable at full-back as well as centre-field and handled him well.
In general Down pushed men forward but found it hard to break down Derrys wall of defenders.
KEY BATTLE
Kevin Johnston (Derry) v Kevin McKernan (Down)
One of the few traditional numerical match-ups (along with both teams sixes v elevens) produced a great battle. Downs McKernan had the early edge, and kicked two terrific points, but Johnston got forward regularly for Derry too.
The Dungiven man set up one Mark Lynch point and was involved in Derrys last two scores, his skewed shot leading to Cailean OBoyles point before being fouled for the free with which Eoin Bradley won the match.
