Two goals up after 20 minutes and seemingly cruising, the Light Blues proceeded to then miss a penalty and allowed United to claw their way back into the match in which they had previously contributed next to nothing.
A fiery second half – with Billy Dodds reducing the deficit 10 minutes after the re-start – saw Rangers toil and some profligate finishing from the Light Blues had the home fans chewing their fingernails until ref John Underhill finally brought play to a close.
Injuries had forced Alex McLeish to once again send out a patched-up side minus six key players but they started the game full of purpose and intent, attacking United from the off.
After being told by his manager to pull his socks up – quite literally – Nuno Capucho looked lively in a central striking role.
He saw a shot cannon off Paul Gallacher’s legs after just 12 minutes but got the goal his play had deserved just five minutes later.
Fernando Ricksen it was who sent the Portuguese striker scampering clear of the static United defence before sweeping a low shot past the goalkeeper.
Three minutes later and the Light Blues doubled their advantage. Michael Mols’ reverse ball sent Chris Burke free on the right and his dangerous cross was toed over the line from close range by Peter Lovenkrands.
With United’s porous defence opening up at every turn, Rangers – for the first time in months – looked like scoring a hatful.
They had the ball in the net again after 25 minutes after a flowing move involving Michael Ball, Capucho and Mols only for a raised linesman’s flag to curtail the celebrations.
A Mark Kerr volley that flew just wide hinted at some fleeting resistance from the visitors but the match should have been over as a contest six minutes later when Rangers were awarded a penalty after Lovenkrands was chopped down by Kerr.
With regular taker Mikel Arteta out injured and no-one else seemingly wanting to take it, Emerson finally took the responsibility but saw his kick well saved by Gallacher.
That was the last piece of action of the first half but the second half started with a crackling burst of controversy.
Under the challenge of Zurab Khizanishvili, Dodds fell to the ground looking for a penalty but saw his claims waved away, much to his manager Ian McCall’s disgust who flapped his arms about in a whirr as if he were trying to take off.
Dodds’ reaction to the referee’s decision seemed to involve him committing a series of pathetic fouls on his former team-mates including one petulant boot at Ricksen that saw him receive a yellow card although it could have been red.
Buoyed by the let-off, Dodds then hauled United back into the game when he scraped home a shot from a matter of yards after an Andy McLaren corner wasn’t properly cleared.
To add insult to Rangers’ injury, at first glance it looked like it shouldn’t have been a corner in the first place.
For the first time in the match the Light Blues’ dominance was suddenly in question although they should have had another penalty when Burke was clattered just inside the box by Kerr.
Ref Underhill, who was well off the pace, chose to give a free kick just outside with no help from his assistant who was a matter of yards away and it came to nothing.
After being in a position where they were easing to victory, things suddenly didn’t look too comfortable for Rangers as United sensed a way back into the match.
McLeish reacted by freshening it up with three changes – including 19 year-old striker Darryl Duffy who made his league debut – but Rangers seemed to have lost the momentum and could only hirple through to the final whistle.
It could and should have been a lot less taxing for the Light Blues but taking all three points was the most important aspect of the afternoon’s work.
RANGERS (4-4-2): 1 Klos; 2 Ricksen, 15 Khizanishvili, 25 Berg, 18 Ball; 30 Burke (Vanoli 86), 8 Hughes, 4 Emerson (Malcolm 75), 26 Lovenkrands; 20 Capucho, 10 Mols (Duffy 82)
Subs not used: McGregor, Ross
Booked: Ball (88)
DUNDEE UNITED (4-4-2): 1 Gallacher; 21 Wilson (Easton 46), 25 Innes, 19 McCracken, 5 Archibald; 14 Dodds (Samuel 74), 4 McInnes, 8 Kerr (Miller 68), 11 Robson; 22 McLaren, 10 McIntyre
Subs not used: Jarvie, Paterson
Booked: Innes (17), Wilson (21), Dodds (47), McCracken (57), Robson (90)
Man of the Match: Henning Berg