It was a dramatic evening at Ibrox and Callum Davidson’s side join Hibs and Dundee United who had already qualified for the final four in the earlier games of the last eight in the national competition.
It was a tight quarter-final between the Perth side and the Scottish champions and it required 120 minutes of football and spot-kicks to separate them and decide upon the penultimate round’s make-up.
Here’s all you need to know ahead of the semi-finals.
When are the semi-finals?
The matches will be played at Hampden on the weekend of May 8 and May 9. That’s a rescheduled date from the previous Scottish Cup schedule which lined the games up on April 10 and 11 before the Scottish Cup’s suspension earlier in the year. May 8 was originally planned as the showpiece final itself.
Premier Sports will show both penultimate games, and the final which will now be played on May 22.
When is the semi-final draw?
Saints became the third team in the semi-final mix and the last spot will be decided on Monday night when Kilmarnock meet St Mirren.
The semi-final draw will be made after the game at Rugby Park – either at 9.30pm or around 10.15pm if the game goes to extra-time and penalties as two of this weekend’s matches did.
How can I watch it?
The draw will be televised on BBC Scotland – who also show Kilmarnock v St Mirren from 7.30pm. It will also be available online via BBC iPlayer.
Kick off is 7.45pm.