Jimmy Calderwood's wait for a home win against Celtic ended in spectacular style as Aberdeen successfully completed part one of their Old Firm double bill at Pittodrie yesterday.
The Dons manager set his side the target of beating both Celtic and Rangers in back-to-back home matches and his players responded in pulsating fashion to give him his first home victory against the Hoops and the Reds’ first since December 2001.
Aberdeen, with five consecutive home wins behind them, were clinical in the final third as they dismantled a woeful Celtic backline with ease. It is not often Rangers are grateful to the Dons but, thanks to this result, Celtic's lead at the top of the SPL is now down to two points.
The bad news is the Light Blues have to travel to Pittodrie this weekend and try to succeed where their great Glasgow rivals failed yesterday.
A scrappy opening 20 minutes suggested little of the drama which was to come, with Stuart Duff, Gary McDonald, Darren Mackie and Mark Kerr cancel ling out the Celtic midfield, and neither goalkeeper was tested.
When the Dons eventually did get it right in the final third, the terrific execution was matched by the simplicity of the build-up. It was Duff who was the architect, collecting the ball wide left, driving forward 10 yards and then curling the ball into the box to Gary McDonald, who rose unchallenged to send a looping header over Mark Brown, who was named in the Celtic starting line-up after Artur Boruc injured himself in the warm-up.
First blood to Calderwood's men but their lapse in concentration to concede an equaliser less than 60 seconds later was unforgivable.
From the restart, Celtic fed Aiden McGeady on the left flank and he spun away from Foster far too easily before racing into the box where he cut the ball back for Scott Brown to score.
Celtic coach Neil Lennon raced 20 yards on to the pitch to cele-brate the goal which was a somewhat foolish gesture given the coaching staff's involvement in past incidents at Pittodrie which caused his manager to be ordered from the dugout, but the Dons silenced him with a terrific second goal in the 31st minute.
With Stephen McManus off the field receiving treatment, the Celtic captain could only watch from the sidelines as Charlie Mulgrew's delivery was cleared only as far as Kerr, and he crossed the ball into the box to Duff, who connected magnificently with a first-time volley which flew past the badly exposed Brown.
Kerr was perhaps a tad fortunate to be on the pitch after he was yellow-carded for a crunching foul on Andreas Hinkel, but there was no repeat of the moment of madness following the opening goal as Aberdeen kept their concentration to reach half-time with their lead intact.
The first 45 minutes had been a time for Aberdeen to ask questions of the Celtic defence but the roles were reversed for the second period with the Dons forced on to the back foot.
The home side didn't help their cause by sitting too deep and inviting pressure. McGeady was again at the heart of all that was good from the champions in an attacking sense.
For all Celtic's pressure, however, they failed to beat Jamie Langfield but with 25 minutes remaining, Jan Vennegoor of Hesselink was sent on for the ineffective Georgios Samaras.
The Dons eventually cracked under the unrelenting one-way traffic.
With the home side camped in their own penalty area, Barry Robson, playing in the left back position for Celtic, pushed forward down the left and crossed the ball to Scott McDonald, who headed past Langfield.
It looked as if the goal would be the turning point of the game but the shock of conceding for a second time roused Aberdeen from their second-half malaise, and with their first foray forward, they took the lead for the third time, with Zander Diamond heading Mulgrew's free kick into the net.
There was a moment where it seemed the goal would not be given but referee Dougie McDonald eventually gave the goal, despite protests from the visitors.
Incredibly, the same duo combined again to make it 4-2, with Diamond knocking in Mulgrew's inswinging free kick at the back post.
On a day when little went the way of the champions, Celtic manager Gordon Strachan will have much to ponder, especially in defence.