Match ends, Aberdeen 0, Kilmarnock 2.
Aberdeen 0-2 Kilmarnock
Greg Stewart returned to haunt his old club as Kilmarnock beat 10-man Aberdeen for the first time in 21 games.
Michael Devlin was sent off after just five minutes for pulling back Eamonn Brophy 30 yards from goal.
It was a decision which infuriated Aberdeen, with referee Craig Thomson deeming Devlin to be the last man.
Kilmarnock took full advantage with Brophy giving them the lead with a free-kick, before Stewart ensured the three points when he chipped a second.
Steve Clarke's men move up to second in the Premiership, with only Hearts - who beat them last week after Gary Dicker was controversially red carded - above them.
For Aberdeen, though, it is just one win in four in the league, and with Devlin now suspended - coupled with injuries to Scott McKenna, Mark Reynolds and Tommie Hoban - manager Derek McInnes finds himself with a defensive crisis.
Kilmarnock re-write the script
Pre-match, Kilmarnock boss Clarke spoke about Aberdeen always finding a "winning moment" to edge close games against them.
The Dons began the day looking to extend an 18-game unbeaten league run against the visitors, 20 in all competitions. But five minutes in it would have been long odds on that record continuing.
Devlin hauled back Brophy with the Killie striker hurtling towards goal. The Dons felt they had plenty of red shirts back to cover, but referee Thomson had no hesitation in reaching for the red card.
Aberdeen were briefly rocked. Aaron Tshibola's header was pushed wide from the resultant free-kick and Brophy soon had a 25-yard shot off the bar. Dons goalkeeper Joe Lewis also had to deny Chris Burke twice in quick succession.
But the hosts appeared to have weathered the storm and were even galvanised by what they saw as a sense of injustice. They hunted Killie in packs.
Every infringement from their opponents was met by howls of protest from those in red. Niall McGinn could even have given them the lead before his free-kick was tipped away from the top corner by Jamie MacDonald.
It almost took them to half-time, until former Don Stewart won a free-kick, and Brophy drove the ball from distance inside the near post to break the deadlock.
Brophy was at the centre of everything. Another free-kick was deflected over, while he had attempts from both sides of the box. He was having free reign to terrorise at every opportunity and Aberdeen's makeshift defence could not cope.
Still the game was alive until Stewart raced clear on the counter attack and chipped Lewis to put the visitors firmly in control. It was a sweet moment for the midfielder on his Kilmarnock debut, having failed to make a significant impact on-loan at Aberdeen last season.
A day of ironies - analysis
BBC Scotland's Liam McLeod at Pittodrie
Aberdeen had been Kilmarnock's bogey team for some time now and they perhaps owe experienced referee Thomson some kudos for that almost six-year run coming to an end.
Football is littered with ironies and Pittodrie was the scene for two as Devlin took over from Killie's Dicker as the unfortunate victim of a dubious red card that came as some were still taking their seats.
Dicker's recent appeal failed and manager Clarke argued that was because the Scottish FA had awarded Willie Collum - who sent Dicker off against Hearts - the Old Firm derby at Celtic Park. Aberdeen will also surely appeal against Devlin's misfortune although the process appears to be as unpredictable as anything in Scottish football.
Once Thomson had decided it was foul a red card was always a possibility as Brophy had begun to race through on goal.
Killie still had to get the job done and they went about their business with purpose and poise. Brophy's goal was outstanding albeit Dons' captain Graeme Shinnie was apoplectic at the free-kick's award.
And Stewart added to the ironic nature of the afternoon as he outpaced the Dons defence on the counter attack and clipped cleverly over Lewis to bring an end to Killie's gruesome record against Aberdeen.
'We can't get over excited' - Clarke
Aberdeen manager Derek McInnes: "Whether it's a red card or not I'm not going to criticise too much. It's harsh on us.
"The important part is the first goal, the handball, it's bad control, he [Stephen O'Donnell] has played it up to his own arm. It should never be a free-kick and we're as disappointed with that as anything today.
"Had we got a result today it would have been a solid start. No shame in losing to Burnley, into the quarter-finals of the league cup, two of those four games were against Hibs and Rangers which are always tough games. What worries us is that consistency of selection, we're not getting it at the minute."
Kilmarnock manager Steve Clarke: "We won the game quite comfortably. We could have had a few more goals. Eamonn Brophy did a great job for us up top. Even with 10 men, I thought Aberdeen were still a threat, they didn't stop trying, they kept putting the ball in the box.
"We can't be over excited just because we've won at Aberdeen. It's been a long time coming so Kilmarnock fans will enjoy that. Seven points from the first four games is less than I wanted, it's less than I thought we would get."
- 2LoganBooked at 87mins
- 18DevlinBooked at 5mins
- 3ShinnieBooked at 83mins
- 8GleesonSubstituted forBallat 6'minutes
- 10McGinnSubstituted forCosgroveat 60'minutes
- 19FergusonBooked at 54mins
- 17MaySubstituted forAndersonat 75'minutes
- 27TshibolaBooked at 30minsSubstituted forMcKenzieat 89'minutes
- 6PowerBooked at 22mins
- 11JonesSubstituted forNdjoliat 79'minutes
- 19StewartSubstituted forWilsonat 73'minutes
- 25BrophyBooked at 56mins
- Craig Thomson
- Shots on Target
Second Half ends, Aberdeen 0, Kilmarnock 2.
Foul by Eamonn Brophy (Kilmarnock).
Max Lowe (Aberdeen) wins a free kick on the right wing.
Attempt missed. Bruce Anderson (Aberdeen) right footed shot from outside the box misses to the left.
Lewis Ferguson (Aberdeen) wins a free kick in the attacking half.
Foul by Rory McKenzie (Kilmarnock).
Substitution, Kilmarnock. Rory McKenzie replaces Aaron Tshibola.
Foul by Kirk Broadfoot (Kilmarnock).
Bruce Anderson (Aberdeen) wins a free kick in the defensive half.
Shaleum Logan (Aberdeen) is shown the yellow card for a bad foul.
Mikael Ndjoli (Kilmarnock) wins a free kick in the defensive half.
Foul by Shaleum Logan (Aberdeen).
Foul by Mikael Ndjoli (Kilmarnock).
Lewis Ferguson (Aberdeen) wins a free kick in the defensive half.
Graeme Shinnie (Aberdeen) is shown the yellow card.
Greg Taylor (Kilmarnock) wins a free kick in the defensive half.
Foul by Graeme Shinnie (Aberdeen).
Greg Taylor (Kilmarnock) wins a free kick on the right wing.
Foul by Gary Mackay-Steven (Aberdeen).
Substitution, Kilmarnock. Mikael Ndjoli replaces Jordan Jones.
Attempt missed. Sam Cosgrove (Aberdeen) left footed shot from outside the box misses to the left.
Substitution, Aberdeen. Bruce Anderson replaces Stevie May.
Kirk Broadfoot (Kilmarnock) wins a free kick in the attacking half.
Foul by Lewis Ferguson (Aberdeen).
Substitution, Kilmarnock. Iain Wilson replaces Greg Stewart.
Attempt missed. Kirk Broadfoot (Kilmarnock) header from the centre of the box is too high.
Corner, Kilmarnock. Conceded by Joe Lewis.
Attempt saved. Jordan Jones (Kilmarnock) right footed shot from the left side of the box is saved in the bottom right corner.
Corner, Aberdeen. Conceded by Jamie MacDonald.
Goal! Aberdeen 0, Kilmarnock 2. Greg Stewart (Kilmarnock) left footed shot from the centre of the box to the top right corner.
Corner, Kilmarnock. Conceded by Dominic Ball.
Attempt missed. Greg Stewart (Kilmarnock) left footed shot from outside the box misses to the left.
Attempt missed. Greg Stewart (Kilmarnock) right footed shot from outside the box misses to the left.
Substitution, Aberdeen. Sam Cosgrove replaces Niall McGinn.
Attempt missed. Stevie May (Aberdeen) left footed shot from the left side of the box misses to the right.
Chris Burke (Kilmarnock) wins a free kick in the defensive half.
Foul by Dominic Ball (Aberdeen).
Corner, Kilmarnock. Conceded by Shaleum Logan.
Attempt blocked. Eamonn Brophy (Kilmarnock) right footed shot from a difficult angle and long range on the right is blocked.