Aberdeen failed to put distance between themselves and third-placed Motherwell in the Scottish Premiership after they were beaten by Partick Thistle on Saturday.
Conrad Balatoni put the Jags ahead near the hour mark before Lyle Taylor doubled Thistle's lead moments later.
Adam Rooney pulled a goal back for the Dons, who may rue Barry Robson's missed penalty in the first half, before Taylor scored his second to seal the points for the Strathclyde club.
Inverness Caledonian Thistle closed the gap on the chasing pack behind Celtic with Gary Warren scoring the only goal before half time in a 1-0 win at St Johnstone, who remain sixth.
Hibernian drew level on points with St Johnstone after drawing with Kilmarnock. Rory McKenzie's 20th minute strike for the hosts was cancelled out by Danny Haynes's second half equaliser.
Ross County put further daylight between themselves and Premiership strugglers St Mirren with a 2-1 win, thanks to goals from Yoann Arquin and Melvin De Leeuw in either half.
Results in full: Hearts 0-2 Celtic, Kilmarnock 1-1 Hibernian, Partick Thistle 3-1 Aberdeen, Ross County 2-1 St Mirren, St Johnstone 0-1 Inverness CT