Alex Rae and Michael Mols were the goal heroes but Andy Goram was once again outstanding with a big save at a vital time and Rangers were worth their win.
The cutely held onto the ball for the closing moments off the game to claim their place in the last four of the tournament they last won in 2008.They will now play ES Top Class.
It was Alex Rae who gave Rangers the lead when keeper Alan Fettis could not hold his fierce right foot shot and it squirmed over the line before Fettis could get a second touch.
However Citbank levelled through former Blackburn Rovers striker Matt Jansen and Rangers were under pressure from the side filled with former Premiership players.
Luis Boa Morte was their main star having played for West Ham only two years ago and he thought he had scored just a few moments later but Goram made a fantasgic block pushing the ball onto the post and wide.
It was vintage Goalie and Rangers took heart from that and moved into the lead just before half-time.
Mols, who had blasted a hat-trick yesterday against KCC Vets, slammed a right foot low into the left corner after a swift break from the back by Rangers just before half-time.
One-time Rangers player Marcus Gayle was also in the Citibank side along with ex-Sunderland defender Michael Gray, who also had a spell with Celtic, but neither could make any impact.
Boa Morte can close when his left foot shot smacked off the base of the post but Rangers were resolute in the closing moments and held on to march on into the semi-finals.
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