Bottom side Dumbarton suffered another disappointing afternoon as they were thrashed 5-1 by Morton.
The visitors - the only side in the division with an unbeaten away record - went ahead after just three minutes, as Martin Hardie scored from the spot after Jamie Ewings had brought down David Graham.
Hardie headed in from Graham's 17th minute corner to score his second of the game.
Peter Weatherson made it three in the 37th minute after meeting Scott Taggart's cross with a well-placed header.
Graham netted the fourth nine minutes after the interval as his corner from the left evaded everyone and found its way into the net.
Weatherson found the bottom corner from 18 yards just after the hour-mark for his second of the afternoon.
Bryan Prunty grabbed a late consolation for the home side with a low drive from the edge of the penalty area.