St Mirren missed the chance to jump up to fourth spot in the Premiership after a fruitless Friday night trip to the capital.
In front of a packed Tynecastle, the Buddies were comfortable throughout the first half but found themselves behind at the break after a slick move saw Barrie McKay curl the hosts in front.
The Saints pressed hard for a second half leveller, with Hearts keeper Zander Clark pulling off a superb double save to deny both Greg Kiltie and Curtis Main.
