A double by forward Brian Graham clinched the points that took Jim McIntyre’s side up to third in the Premiership table, with the attacker netting his first league goals with two opportunistic finishes.
Aberdeen were thwarted in their attempts to get back into the game by a resolute County defence, marshaled by the outstanding captain Andrew Davies but, in truth, the Staggies could have inflicted further damage had Liam Boyce taken one of a number of chances afforded to him.
The defeat means Aberdeen will be knocked off the Premiership summit if Celtic take at least a point from their game against Motherwell this afternoon.
County were defeated 2-1 by Highland rivals Caley Thistle in their last match and made three changes from that team.
A switch between the sticks was enforced, with Gary Woods replacing the injured Scott Fox, while captain Davies and left back Jamie Reckord also returned in place of Scott Boyd and Jonathan Franks, meaning former Don Richard Foster occupied a position on the wide left of midfield.
Aberdeen went into the game on the back of three straight losses, with manager Derek McInnes making four changes from the side thrashed 5-1 by St Johnstone in its last outing.
Captain Ryan Jack missed out with a sickness bug, while Shay Logan, Peter Pawlett and Adam Rooney also dropped out.
Taking their places were Paul Quinn, to face the side he captained to safety last season, along with Willo Flood and David Goodwillie. The most notable returnee was Mark Reynolds, though, who made his first appearance since he sustained a shoulder injury in the Europa League tie against Shkendija in Macedonia on October 2. The defender captained the side in Jack’s absence and formed part of a 3-5-2 formation.
Prior to the match, Dons supporters unfurled a banner to show their resentment to the actions of Premiership sponsor Ladbrokes, which triggered a frenzy of social media speculation this week by suspending odds on McInnes being the next top-flight manager to leave his post.
Aberdeen were first to threaten when Niall McGinn tried his luck from long range, his driven effort held by Woods. At the other end, Boyce’s low effort lacked enough power to trouble Danny Ward after he was teed up by Stewart Murdoch.
Goodwillie was given a sniff at goal on 16 minutes after being set up by Graeme Shinnie, but he sent his drive just wide of the left-hand post from the angle of the penalty area.
The Reds survived a double let-off midway through the first half. With a Foster corner causing chaos, the defence scrambled clear point-blank efforts from Graham and Chris Robertson.
An even better chance fell the way of leading scorer Boyce moments later, though, as he cut inside his marker to go clean through before slipping as he dragged his shot wide.
The Staggies began to take firm control and Boyce went close again when his header from a Foster cross was well held by Ward.
It looked only a matter of time before the hosts took the lead and, when the impressive Foster was released in acres of space down the left channel before cutting inside, Quinn’s intervening tackle fell for Graham to stab the ball home from 10 yards to give his side a deserved lead.
McInnes rang the changes at half-time, bringing on Logan and Rooney for Reynolds and Flood.
There was to be no stopping Graham doubling County’s advantage just five minutes into the second-half, however.
Quinn misjudged a long ball to allow Graham in, before the attacker got the break of the ball off Ash Taylor and curled neatly past Ward to leave the Dons in disarray.
The visitors were inches away from pulling one back four minutes later when McGinn struck a low drive off the post before the ball fell for Rooney, whose follow-up was hacked clear by Reckord – a sure sign it was not the Reds’ night.
Rooney was again thwarted when Woods made a fantastic save with his legs, after the Irishman diverted Jonny Hayes’ free kick goalwards.
The scoreline could have been harsher on the Dons had Boyce brought his shooting boots, the Northern Ireland international missing three superb chances in the second half. The Stagges, however, held on for a well-deserved victory.