The leading trio in League 1 all won on Saturday and are separated by just a single point with six matches remaining.
Frontrunners Stranraer beat Airdrieonians 1-0 at Stair Park thanks to a Willie Gibson goal with just seven minutes remaining.
Morton claimed a dramatic 2-1 victory over Ayr United at Cappielow. Jon-Paul McGovern gave Ayr the lead but Declan McManus equalised in the last minute and Ross Forbes grabbed an injury-time winner for Jim Duffy's men.
Forfar stay third after a 3-2 win at Glebe Park against a Brechin side just below them in the table. Derek Young, Chris Templeman and Darren Dods scored for Dick Campbell's team, with Paul McLean and Andy Jackson on target for City.
Dunfermline are three points outside the top four thanks to a 1-0 win against Stenhousemuir at Ochilview. Faissal El-Bakhtaoui got the only goal just after half-time for the Pars.
Bottom club Stirling Albion recorded their first home win in League 1, beating Peterhead 2-1 at Forthbank. On-loan Andy Stirling scored late on after Lewis Coult had cancelled out Rory McAllister's early opener.