Dundee continue to dominate the Tayside derby and took all three points as, yet again, Ian McCall was outsmarted by Jim Duffy in the tactical battle.
Still to find an elusive win over his neighbours, McCall saw his team dominate possession but be exposed on the break and also to some harsh refereeing decisions.
This was no excuse however, as his team were clearly guilty of wasting chances and some dreadful defending.
The game started off at a lightning pace which referee Hugh Dallas tried to temper with a yellow card to Steven Robb in the seventh minute.
It was United, however, who created the first chance in the 12th minute when a deep Barry Robson cross was flicked back by Jim McIntyre for Billy Dodds to shoot. But the outstretched arms of Derek Soutar brilliantly clawed the ball away.
There was mayhem in the 16th minute when referee Hugh Dallas astonishingly awarded a penalty for David McCracken's tackle on Iain Anderson.
Without any claim the official immediately pointed to the spot. After calming down the infuriated United players the ball was given to Steve Lovell, whose kick was partially blocked by Tony Bullock, only for the ball to slide over the line.
United responded with vigour with Mark Wilson's free-kick testing Soutar in the 26th minut,e then McIntyre lashing just wide from an acute angle. Then, following a goalmouth scramble, Alan Archibald's 33rd net-bound volley came off the back of Brent Sancho.
As the pressure intensified Sancho was fortunate in the 35th minute when the ball struck his arm in the box but the referee was unsighted.
Two minutes later Soutar pulled off yet another great save from Robson's thunderous 20-yard shot, turning the ball round the post. Three minutes from the break, Dallas, who had been having a poor game, shook his head as the United support screamed for a penalty when Sancho nudged McIntyre in the back.
Barely had the game restarted when John Sutton made it two. Lovell easily beat McCracken on the right flank and drilled a low ball in at the near post for Sutton to catch out a static Terrors defence and poke the ball through the legs of Bullock from six yards.
A shell-shocked United hit back with Dodds' header being nodded off the line by Anderson.
The pressure continued but despite having numerous chances the Tangerines could not breach the Dee's defence until injury time, when Archibald headed in Wilson's corner.