Aberdeen lost ground to Premiership leaders Celtic as they slipped to a disappointing 1-1 draw at home to struggling Kilmarnock.
Victory for the Reds would have kept Derek McInnes’ side level on points at the top of the table with defending champions Celtic.
However they slipped up against Kilmarnock, a side the Dons had defeated in their previous 13 matches.
It was a wasted opportunity for the Reds who must now lick their wounds ahead of the League Cup quarter-final trip to Motherwell on Thursday.
Summer signing Stevie May put the Dons ahead early on but the expected win failed to materiialise as Jordon Jones levelled early into the second half.
Icelandic international Kari Arnason was given his first game time since the 2-0 win over Hamilton on the opening Premiership match of the season.
The 34-year-old centre-back was pitched in from the start as Dons boss Derek McInnes made three changes to the side that drew 0-0 with Hearts at Murrayfield last weekend.
On loan Celtic attacker Ryan Christie, striker Adam Rooney and on loan Rotherham defender Dominic Ball dropped to the bench with Arnason, Greg Stewart and Nicky Maynard coming in.
Aberdeen grabbed a deserved lead in the 10th minute when captain Graeme Shinnie drilled a cross deep into the penalty area.
Summer signing Stevie MAY controlled the ball then lashed home a superb left footed drive from about 10 yards out.
It was a superb finish and underlined why the Reds were willing to splash out £400,000 to sign the Scotland cap from Preston North End in the recent transfer window.
May was involved again soon after when his inswinging free-kick picked out Andy Considine racing in on goal but the left-back headed over from 15 yards.
In a rare foray up-front Stephen O’Donnell headed a corner kick over at the near post in the 25th minute.
Moments later Killie registered their first shot on target when Jordan Jones fired in a low drive from 22 yards but keeper Joe Lewis comfortably smothered the effort.
Keeper Lewis recreated his Murrayfield heroics with another superb save when diving to his right to push a vicious Rory McKenzie 22 yard strike wide in the 35th minute.
Kilmarnock stunned Aberdeen in the 48th minute. Following impressive build up play from the visitors Jordan JONES received possession 20 yards out and unleashed a superb shot that flew beyond Lewis.
In the 55th minute winger Scott Wright crossed to the far post but Stewart, stretching to meet the ball, headed well wide from six yards.
Aberdeen were living dangerously and the wood-work denied Killie in the 58th minute as Stuart Findlay latched onto a Jones corner kick and his looping effort crashed off the top of the bar with Lewis beaten.
Dons boss Derek McInnes immediately moved to try and change the momentum of the game by introducing substitutes Ryan Christie and Gary Mackay-Steven to inject pace and creativity.
Nicky Maynard and Greg Stewart were replaced.
Christie was immediately involved when he attempted to curl a 20 yard effort beyond keeper Jamie Macdonald with the outside of his boot.
The effort flashed inches wide of the far post.
Aberdeen were looking blunt in attack and Kenny McLean blasted a speculative 25 yard effort well over in the 73rd minute as the Reds struggled to break down a resolute Killie back-line.
McLean had a diving header at the near post saved from close range then moments later May fired in a 35 yard shot that had the keeper beaten only to flash inches wide.
In injury time keeper Macdonald pushed a 25 yard free-kick from May over the bar as the Reds failed to make the breakthrough as the Reds winning run against Killie petered out.
ABERDEEN: Lewis, Logan, Shinnie, Considine, O’Connor, McLean, Stewart, Maynard, Arnason, Wright, May.
SUBS: Christie (for Maynard 58 ), Stewart (for Mackay-Steven 58), Rooney (for Wright 84)
SUBS NOT USED: Rogers, Reynolds, Tansey, Ball.
KILMARNOCK: Macdonald, O’Donnell, Greer, McKenzie, Jones, Taylor, Findlay, Waters, Wilson, Frizzell, Erwin.
SUBS: Hawkshaw (for Wilson 22), Burke (for Jones 90)
SUBS NOT USED: Bell, Broadfoot, Thomas, Boyd.
Referee: Stephen Finnie.