Dundee piled misery on Aberdeen as goals by Tom Cowan and Nacho Novo earned them a 2-0 victory.
The game started off a bit scrappy with both teams given the ball away far too easily. Juan Sara saw a curling left foot effort go inches past the upright with 17 minutes played.
Midway through the first half, David Zdrilic shot well wide of the target from 25 yards.
Juan Sara missed a golden opportunity to put his team ahead after 25 minutes, but he shot wide from three yards with only David Priest to beat.
Dundee did go in front however with 28 minutes played when Cowan scored on his debut.
A shot by Fabian Caballero was charged down by an Aberdeen defender and the ball broke kindly to Cowan who fired a cracking left foot shot high past David Priest from 30 yards.
The visitors were rewarded a penatly kick ten minutes before half time when Lee Wilkie fouled Fergus Tiernan inside the box.
David Zdrilic stepped up to take the kick only to crash his effort off Julian Speroni's left-hand post with the keeper diving the right way.
Dundee were then denied by the woodwork when Fabian Caballero crashed a shot off the post five minutes before half time.
David Priest made an excellent save to deny Gavin Ray 10 minutes into the second half.
Gavin Rae again threatened the Aberdeen goal but he fired just wide of the target from 12 yards with 20 minutes remaining.
Lee Wilkie's last ditch tackle saved Dundee when Aberdeen sub Leigh Hinds ran in on goal with 12 minutes to go.
Dundee went 2-0 up with 9 minutes remaining when Barry Smith's quick free kick left the Aberdeen defence standing and Novo raced in on goal and kept his cool to slot past David Priest from 10 yards.
That secured the points for Dundee but there was still time for Julian Speronli to deny Paul Shearin in the final minute with his first save of the match.