Central Coast Mariners' poor recent run continued as the A-League leaders slumped to a 1-0 defeat at Melbourne Heart.

Eli Babalj struck the only goal of the game in the 50th minute as the Mariners suffered their third loss in their last five games, having previously lost only twice this season.

The result means the Mariners are now just three points ahead of second-placed Brisbane Roar, who have won their last four matches, including yesterday's 3-0 win at Perth Glory.