A highly controversial goal on the stroke of half-time proved a body blow to the Tangerines at Dumbarton’s Bet Butler Stadium tonight.
Having created by far the better chances in the first half, United went in trailing a more experienced Rangers side at the break who capitalised on their good fortune in the second half.
With just four minutes gone, the visitors were first to threaten, Rangers keeper Liam Kelly being at full stretch to tip a Calum Butcher drive from just outside the box round the post.
And it was Kelly to the rescue again eight minutes later when he palmed Scott Lochhead’s rising shot over the bar.
United continued to have much the better of the chances and it wasn’t until ten minutes from the interval that Michal Szromnik was tested fielding a low grounder from Nicky Clark.
So it was against the run of play that the Ibrox side took the lead two minutes later thanks to a dipping 30-yarder from Andy Murdoch.
However, the Tangerines were level two minutes from the break, Ryan Sinnamon, under pressure from Aaron Duke, turning a Reghan Tumilty corner into his own net.
But right on half-time, Rangers regained the lead when the referee ruled that Greg Pascazio’s header counted, despite skipper Euan Spark seemingly clearing the ball before it crossed the line.
Only two fine Szromnik stops prevented the hosts adding to their score before Fraser Aird angled a free-kick into the top corner for the third midway through the second period.
Four minutes from the end, Murdoch scored his second and his side’s fourth, drilling home from 15 yards.
Dundee United: Szromnik, Watson, Spark, Butcher, Wilson, H Souttar, Tumilty (Montgomery 78), B Smith, Adeyemo, Duke, Lochhead. Subs not used: Booth, McLaughlin, Robson, Horne, McNaughton, M Smith.