Steven Thompson's 89th-minute winner saw St Mirren defeat 10-man St Johnstone 4-3 in a roller-coaster game at St Mirren Park.
Substitute Rory Fallon thought that he had given his side a point with an 84th-minute leveller, but St Mirren left it late to snatch all three points in their Scottish Premiership clash.
Elsewhere, Calvin Zola's second-half goal saw Aberdeen defeat Dundee United 1-0, while Shaun Hutchinson's 83rd-minute winner helped Motherwell triumph 2-1 at home to Hearts.
Kilmarnock eased to a 2-0 victory over Ross County thanks to goals from Kris Boyd and Jackson Irvine.
In the day's early kickoff, Celtic were held to a 1-1 draw at Hibernian.
Results in full: Hibernian 1-1 Celtic, Aberdeen 1-0 Dundee Utd, Kilmarnock 2-0 Ross County, Motherwell 2-1 Hearts, St Mirren 4-3 St Johnstone
