It seems reports of Aberdeen’s demise as the best of the rest in Scottish football have been premature.
On an afternoon which saw Steven Gerrard suffer the most painful setback so far of his managerial tenure at Rangers, the man who turned down the Ibrox post celebrated reaching his fourth major final in charge of Aberdeen.
The sweetest of victories for Derek McInnes and the Pittodrie club was secured by a player steeped in Rangers heritage.
Lewis Ferguson, son and nephew of former Ibrox heroes Derek and Barry respectively, scored the only goal of an often attritional Betfred Cup semi-final with 11 minutes remaining.
It saw Rangers pay the ultimate price for a glaring lack of incision and consistently poor decision making in the attacking third of the pitch.
The absence of the suspended Alfredo Morelos and ineligible Kyle Lafferty was sorely felt by Gerrard’s side.
Umar Sadiq was unable to adequately fill the striking void as the on-loan Roma player made his first starting appearance for Rangers.
Aberdeen defended robustly throughout, even after the loss of Andrew Considine to injury in the first half, to grind out the win which means they will face Celtic in the final on 2 December.
While Rangers were generally the more progressive and cohesive side, a nervy start from central defender Joe Worrall handed Aberdeen the first sight of goal inside the first minute.
The on-loan Nottingham Forest player’s panicky pass just outside his own penalty area saw him give the ball straight to Ferguson.
The Aberdeen midfielder had a clear run on goal, leaving Ovie Ejaria with little option but to pull him down at the expense of receiving the first booking of the match.
Niall McGinn bent the free-kick around the Rangers defensive wall, forcing Allan McGregor into a smart save down low to his left.
• READ MORE - Aberdeen 1-0 Rangers: As it happened
Sadiq’s first opportunity to make an impression came in the fifth minute when he showed good strength and determination to get on the end of a James Tavernier free-kick, sending his header just over.
McGinn should have put Aberdeen ahead in the 14th minute when good link-up play down the right between Gary Mackay-Steven and Scott Wright set up an excellent chance for the Northern Ireland winger.
But with as much time and space as he could have wished for, McGinn’s composure deserted him as he blazed his right foot shot over from around 14 yards.
Rangers made plenty of headway down both flanks as they tried to stretch Aberdeen and Daniel Candeias, after beating Considine with ease on the right, chipped a cross straight to Joe Lewis with the unmarked Sadiq waiting at the far post.
A knockdown from Sadiq created an opening for Ryan Jack, whose every touch was predictably jeered by the Aberdeen fans, but he was unable to punish his former club’s poor marking as he dragged his shot wide of Lewis’ right hand post from just outside the box.
Following a lengthy and worrying delay for treatment to Considine, who was replaced by Max Lowe, Aberdeen threatened when Mackay-Steven’s looping cross looked to be dropping in until McGregor scrambled back to touch the ball onto the bar and over.
Rangers’ best chance so far fell to Worrall in the 43rd minute when Sadiq helped the ball into his path from another Tavernier set piece. The big defender had time to steady himself but drove his shot over the top.
With Gerrard’s side now in the ascendancy, they had a penalty claim turned down in first half stoppage time when Ryan Kent went down under Shinnie’s challenge.
Referee John Beaton was well positioned and saw the Dons captain’s touch on the ball.
Rangers had another shout for a spot-kick dismissed early in the second half when Sadiq tumbled under a clumsy challenge from Scott McKenna as Aberdeen found themselves hemmed into their own half for sustained spells.
Lewis made a fine save to keep out a fierce shot from Tavernier as Rangers tried to bring greater intensity to their work but Aberdeen remained dogged defensively.
Coulibaly scuffed a shot wide from a Tavernier corner, then Kent saw an effort deflected narrowly off target by Shinnie.
There was always a danger to the Ibrox side that their lack of a cutting edge would be punished and so it proved with Ferguson’s 79th minute winner.
Mackay-Steven, always an outlet for Aberdeen in taking some of the pressure off their defence, did well to force a corner kick.
McGinn swung it over from the left and Ferguson rose above both Ovie Ejaria and Connor Goldson to thump a close range header beyond McGregor.
Gerrard made a double substitution in a bid to salvage the tie, with Scott Arfield and Glenn Middleton both entering the fray for the closing stages but neither could provide the inspiration so sorely lacking in Rangers’ play.
The closest they came to an equaliser was when Sadiq knocked the ball beyond Lewis inside the box but, instead of trying to go on and score, went down in a brazen piece of simulation to try and win a penalty.
He was rightly booked for his trouble and Aberdeen saw out the rest of match without any further drama to earn a return journey to Hampden for the final in five weeks’ time.
Aberdeen: Lewis, Logan, Devlin, McKenna, Considine (Lowe 35); Mackay-Steven, Ferguson, Shinnie, McGinn; Wright (May 60), Wilson (Ball 86). Subs not used: Cerny, Gleeson, McLennan, Cosgrove.
Rangers: McGregor, Tavernier, Worrall, Goldson, Flanagan; Coulibaly, Jack (Middleton 82), Ejaria; Candeias (Arfield 82), Sadiq, Kent. Subs not used: Foderingham, Halliday, Rossiter, Katic, Grezda.