Johnny Russell scored a double as Dundee United outclassed nine-man Rangers to knock the fallen Glasgow giants out of the Scottish Cup at the fifth-round stage with a 3-0 win at Tannadice.
Jackie McNamara, who replaced Peter Houston on Wednesday, took his place in the United dugout for the first time and he watched his side get off to a dream start as Russell fired home the opener after just 15 seconds.
The striker then hit the bar before Jon Daly doubled United's advantage with a 36th-minute header, and Russell then grabbed his second of the match 11 minutes from time.
The Ibrox side then lost their discipline as substitute Kal Naismith saw red for a scything challenge on Willo Flood in the 85th minute before he was followed down the tunnel by midfielder Ian Black two minutes later as he picked up his second yellow card.
The win, United's first at Tannadice since August, sends them into Sunday's quarter-final draw and gave Third Division leaders Rangers an indication of how far they have to go as they bid to reclaim their place in the top division of Scottish football.
"It was a terrible start for us and we didn't defend very well for the second goal either allowing a free header to Dundee United," said disappointed Rangers manager Ally McCoist.
"I felt we came in to it in the second half for maybe a 25-minute period and then again in the middle of defence we gave away a very poor third goal."
In contrast, McNamara thought his side were outstanding.
"It is a good feeling at the moment. We have had the transition of moving in here in a short space of time but I thought it was a fantastic occasion for us and the fans were tremendous," he said.
"I hope we can start like that in every game. It gave everyone a lift and I thought in the first half we looked very dangerous and caused them a lot of problems."
The build-up to the tie since the fifth-round draw had been eventful with Rangers deciding not to take up their ticket allocation.
That measure was taken in response to United's opposition to the Ibrox club's application to join the Scottish Premier League last summer after they were liquidated and then reformed -- a decision that ultimately led to the Glasgow side being placed in the bottom tier of the Scottish system.
The large home crowd were eager to see how former Celtic defender and Partick Thistle boss McNamara would fare in his first game in charge, and the hosts got off to a perfect start when Russell netted straight from kick-off.
Daly's header caused confusion between Emilson Cribari and Ross Perry in the centre of defence which allowed the United striker to nip in and fire low under the body of goalkeeper Neil Alexander.
Andy Little came close to equalising for Rangers, before Russell lost his marker to get on the end of Flood's cross, only for his header to bounce just past the post.
The United striker was causing the 'Gers defence all sorts of problems and, when Daly knocked on a free-kick, Russell was on to it in a flash and clipped a shot off the bar.
The Rangers defence were again posted missing as United doubled their lead when Flood found United skipper Daly in acres of space in the box and his header evaded Alexander as it flew into the net.
The intensity of the first half was replaced by a more sedate pace after the break as Rangers dominated possession but lacked an end product.
However, Daly and Russell combined once again to expose their defensive frailities in the 79th minute.
Irishman Daly flicked the ball on for the in-form striker, and he slid it under the advancing Alexander to grab his second of the game.
Rangers then lost the plot as Naismith and Black were sent off within two minutes of each other.