Rangers maintained their four-point advantage at the top of the table with an emphatic victory over Dunfermline, as Celtic overcame Inverness.
Rangers suffered a shock League Cup defeat to first division Falkirk in midweek but they have been in fine form in the SPL so far this season and Steven Naismith scored twice at East End Park to inspire a 4-0 win against Dunfermline.
Celtic, beaten in the first Old Firm derby of the campaign at Ibrox last weekend, kept in touch with their rivals as Joe Ledley and James Forrest scored to condemn bottom club Inverness to a 2-0 loss.
Third-placed Motherwell remain two points further back after Robert McHugh's late effort secured a 1-0 victory over Aberdeen and increased the pressure on their former boss Craig Brown.
Hibernian and Dundee United played out a six-goal thriller at Easter Road but had to settle for a point apiece following a topsy-turvy 3-3 draw.
Paul McGowan's first-half double did the damage for St Mirren in their 3-0 triumph at home to Kilmarnock.