Johnny Russell grabbed a double as Dundee United handed new boss Jackie McNamara the perfect start to the job by dumping nine-man Rangers out of the William Hill Scottish Cup.
Russell struck after just 16 seconds, before Jon Daly doubled the advantage and Russell put the gloss on the fifth round victory, which saw Kal Naismith and Ian Black dismissed late on.
Controversy surrounded the build-up to the tie when Rangers opted against taking a ticket allocation for the match.
The decision was a response to calls from fans groups to boycott what was the first away fixture against Clydesdale Bank Premier League opposition since the club were denied entry to the top-flight after being consigned to liquidation in the summer.
Of the 9,564 crowd inside Tannadice, 365 were recorded as visiting fans, with some Gers supporters opting to take in the match regardless - although they may have been wishing they had not bothered making the trip to Tayside in the end.
Rangers made two changes from the side who drew with Montrose in the Irn-Bru Third Division last week.
Sebastien Faure and Black replaced Chris Hegarty and the injured Lewis Macleod, while Francisco Sandaza was passed fit to start despite concerns over a hamstring injury.
McNamara named an unchanged United side from the one that started predecessor Peter Houston's last match.
The new boss enjoyed the best possible start to his tenure when the home side surged into the lead with just 16 seconds on the clock.
A defensive error by Emilson Cribari allowed Russell to nip through on goal and dispatch a shot beyond the out-stretched hand of Neil Alexander.
Rangers almost levelled straight away when they raced up the park and Dean Shiels teed up the shot for Andy Little, who dragged across the face of goal and just wide.
However, the visitors looked rattled and Russell bulleted a header just wide of target, before seeing another effort crash off the crossbar.
Rangers had another chance to haul themselves back into the tie when Lee Wallace picked out Sandaza in front of goal and his glancing header was not too far away.
Instead, it was United who had the net bulging again after 36 minutes when Daly took advantage of poor defending to rise unmarked in the box and nod home from Willo Flood's free-kick.
There was a further set-back for Rangers when Ross Perry was forced out of the action shortly before the break and was replaced by Hegarty, who has been troubled by thigh spasms in recent weeks.
The Glasgow giants - who swapped Sandaza for Naismith at the break - enjoyed more of the possession after the restart as they tried to rescue the tie.
An impressive half-volley from Black fell just wide of the upright, before David Templeton's low drive was smothered by goalkeeper Radoslav Cierzniak.
United still looked capable of adding to their tally and Russell burst down the right flank before delivering a teasing ball into the box for Daly but Hegarty did well to snuff out the danger before the skipper could connect.
There was no way back for Rangers when Russell claimed his second - and United's third - of the day with 10 minutes to go.
Michael Gardyne nodded down for Daly and he played into the path of Russell to sweep into the back of the net from six yards.
A miserable day was compounded for Rangers when Naismith was shown a straight red for a challenge on Flood after 86 minutes, before Black picked up a second caution for a foul on John Rankin a minute later.