The wing-back netted in both halves and also provided an assist for Ryan Strain’s third goal.

Dundee had won the two previous derbies at the home of their city rivals but this time they were a distant second best.

The result leaves United still comfortably sitting seventh in the Premiership table while Dundee remain five points ahead of Kilmarnock in the relegation play-off spot.

The Terrors had a gilt-edged chance to take the lead in just the third minute when Zac Sapsford pounced on a mistake by Yan Dhanda and then ran through on goal but the Australian striker’s tame shot was easily saved by keeper Jon McCracken.

The visitors then worked their way into a dangerous position but when the ball finally fell to centre-half Luke Graham, he blasted well wide of the target.

Instead, it was the hosts who made the breakthrough in the 14th minute. Ferry teed up Sapsford inside the Dundee box with his tame trundler taking a deflection off Graham before cannoning into Ferry, with the ball hitting the post and then rolling into the net.

The visitors came close to equalising when Dhanda sent a cross into the box towards Graham with his volley looking net-bound until a vital goal line clearing header by Iurie Iovu.

The pendulum swung United’s way once again in the 24th minute when Max Watters found Neil Farrugia with a cross-field pass. The winger cut in and hit a low shot that McCracken made a hash of with the ball bouncing off the inside of the post before being cleared.

Dundee thought they had equalised in the 35th minute when Westley headed home from close range but the away support’s celebrations were cut short when referee Matthew MacDermid was called over to the VAR monitor with the goal disallowed for a handball by Billy Koumetio.

Deep in stoppage time, Dundee skipper Ethan Hamilton tried his luck with a long-range shot but it was well held by home keeper Dave Richards.

There was a quiet opening to the second half with both sides struggling to carve out clear-cut chances.

However, United took total control of the game with two quickfire goals. In the 70th minute Ferry hit a low shot from the corner of the Dundee box which flew into the back of the net off the inside of the post.

Just two minutes later, the Terrors made it three with Ferry sending a superb cross in from the left with Strain bulleting a header past the helpless McCracken.

There was no way back for Dundee with the home fans celebrating the win and the attainment of the city bragging rights at the final whistle.