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:
1. Zander Clark - 9
Shoot-out and extra-time hero also denied Morelos twice before finally being beaten by Tavernier - then ALMOST scoring Photo: Alan Harvey - SNS Group
2. Jason Kerr - 7
Unlucky to be booked when acting peacemaker in first half and showed composure on the ball Photo: Craig Foy - SNS Group
3. Liam Gordon - 7
Tested McGregor with a second half header and was frequent aerial winner at the back up against Morelos. Photo: Craig Williamson - SNS Group
4. Jamie McCart - 7
Shackled Hagi well, but troubled by Kent after second-half switch - still kept Rangers out at Ibrox over 90 minutes for only second time this season. Photo: Mark Scates - SNS Group