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:
9. Scott Tanser - 6
Sweet strike on volley forced McGregor into save and deliveries threatened but off injured in extra-time. Photo: Alan Harvey - SNS Group
10. Stevie May - 7
Willing runner almost scored when shutting Allan McGregor down in the first half hour. Defensive shift second half. Photo: Mark Scates - SNS Group
11. Guy Melamed
Kept pressure on Rangers’ back-line but limited opportunities. Photo: Mark Scates - SNS Group
12. Chris Kane - 7
On for Melamed to add presence in attack but saw little until vitally tapping in Clark’s header. Photo: Craig Williamson - SNS Group