Inverness Caledonian Thistle leapfrogged Aberdeen into second place in the Scottish Premiership with a convincing win at home to Kilmarnock on Saturday.
Aaron Doran's first-half strike put Terry Butcher's men in front and Graeme Shinnie's goal just after the interval doubled their lead.
Darren Barr pulled a goal back for the visitors with 15 minute left, but it wasn't to stop Inverness from taking the points.
Two goals in seven minutes from Paul McGowan and Steven Thompson should have been enough for St Mirren to secure three points against Ross County.
However, heavy rainfall meant resulted in a delay and, despite the best efforts of the Love Street ground staff, the referee called the game off.
Hearts' hopes of an unlikely escape from negative points and relegation suffered a setback as goals from Nigel Hasselbaink and Steve May gave St Johnstone victory at Tynecastle.
The result leaves the Jambo on seven points away from zero and, more importantly, 15 adrift of 11th-placed St Mirren.
Results in full: Celtic 1-1 Dundee United, Hearts 0-2 St Johnstone, Inverness CT 2-1 Kilmarnock, St Mirren P-P Ross County
Chris O'Keefe
