The League Cup winners moved into the semi-finals at Hampden at the expense of the Premiership champions following a dramatic end to a tense encounter.
After a goalless 90 minutes, Rangers captain James Tavernier thought he had won the tie for his side when he headed home the opener in the 117th minute.
However, a last gasp equaliser for St Johnstone’s Chris Kane, after goalkeeper Zander Clark had flicked the ball on from a corner, sent the match to penalties, where Clark was the hero again with saves from James Tavernier and Kemar Roofe before Ali McCann slotted home the decisive spot-kick.
Here’s how the St Johnstone heroes rated:
5. Shaun Rooney - 6
Often Saints’ talisman, faded out of the game after finding some forward joy in first half then burst into life halfway through extra-time. Photo: Rob Casey - SNS Group
6. Ali McCann - 8
Didn’t give Davis a moment to pick a pass and snuffed out Northern Irishman’s influence first half, and disciplined defensive shift in second half to become penalty hero. Photo: Ross Parker - SNS Group
7. Liam Craig - 7
Typical tireless shift ensured Saints’ shape stayed solid and made midfield a busy battleground for Rangers. Set piece threat. Photo: Mark Scates - SNS Group
8. David Wotherspoon - 5
Fortunate to avoid a red card for a reckless first half tackle and unable to create going forward. Set piece threat Photo: Craig Williamson - SNS Group