Championship side Raith Rovers beat Hibernian 3-2 to reach the last eight of the Scottish Cup, despite the Leith club twice coming from behind to level the tie.
Kevin Moon powered the Fife club into a sixth minute lead at Easter Road only to be pegged back by a Samuel Stanton strike for the home side.
Dougie Hill thought he had given Rovers a half-time lead when he rifled his shot home from close range, but in first-half stoppage time Michael Nelson headed home Liam Craig's cross to bring Terry Butcher's side level.
It was left to Grant Anderson to see off the any Hibs revival when he met Joe Cardle's cross to head the ball beyond Ben Williams.
Another Premiership side, Inverness Caledonian Thistle, need to come from behind to earn a replay against League One Stranraer.
Aaron Doran put the Highland club ahead on 40 minutes, but the hosts were level on the stroke of half time thanks to a Martin Grehan penalty.
Jamie Longworth put Stranraer ahead with 18 minutes remaining, but their hopes of a Cup upset were quickly extinguished when Billy McKay making it 2-2 soon after.
St Johnstone made no mistake in sweeping aside Forfar to reach the quarter-finals, with Stevie May, Frazer Wright and Michael O'Halloran all on the scoresheet for the Perth outfit.
James Dunne rounded off the scoring for the visitors, who were rarely troubled en route to the last eight.
Results in full: Forfar 0-4 St Johnstone, Hibernian 2-3 Raith Rovers, Stranraer 2-2 Inverness CT