St Johnstone 1 Rangers 1 (3-4 on pens): Goalkeeper Neil Alexander was the hero as Rangers booked their place in the Scottish Cup final following a tense penalty-shoot out against a battling St Johnstone side.
Alexander — between the sticks for the injured Allan McGregor — saved spot-kicks from both Steven Milne and Jody Morris after Nacho Novo had cancelled out Daniel McBreen's opener in extra-time.
Rangers will now face another First Division side — Queen of the South — at Hampden in the showcase on May 24th.
Only Christian Dailly, Steven Whittaker and Carlos Cuellar — captain for the day in the absence of Barry Ferguson — survived from the defeat at Celtic Park midweek, as Rangers made eight changes.
Some of those were enforced with McGregor and Lee McCulloch sustaining injury on Wednesday night and David Weir suspended for his part in a fracas at the end of the Old Firm derby.
Thomas Buffel had the ball in the net in the first half but his decent finish was correctly flagged for offside.
Novo passed up the best chance of the first half when he pounced on a dreadful pass back from Goran Stanic only for his shot to clip the body of veteran goalkeeper Alan Main and trundle wide of the far post.
Rangers could have all but killed off this turgid tie with 10 minutes to go in normal time when Whittaker raced onto a Davis ball but was denied by Main, who pounced off his line to produce a timely block before the full-back could pull the trigger.
However, they were taken to extra-time by their First Division challengers, whose substitute McBreen finally broke the deadlock with 94 minutes on the clock. Paul Sheerin provided a teasing cross from the left and McBreen connected in plenty of space to dispatch a downward header past Alexander.
Rangers were back on level terms eight minutes later when Cousin was tripped in the box by Gary Irvine and referee Dougie McDonald immediately pointed to the spot.
Novo did the honours from 12 yards and finally breached Main's goal with a finely struck penalty which nestled in the keeper's right-hand corner.
The epic last four clash was eventually decided by a shoot-out, with Alexander saving a penalty from Milne, and Main denying Brahim Hemdani, before the Rangers keeper blocked from Morris to finally secure a place in the Scottish Cup final.