Hearts snatched a dramatic three points at Livingston in their final league encounter before the international break.
Lewis Smith notched after 26 minutes in a dour first-half display from the Jambos, but Derek McInnes' side hit back in the second 45 via Claudio Braga's well taken header.
The Jambos almost snatched a winner ten minutes from time after debut boy Ageu teed Claudio Braga on goal, but agonisingly hit the post.
Deep into added time, substitute Alexandros Kyziridis struck a sublime, curled effort to secure a big three points for Hearts.
It was a frantic start to proceedings in West Lothian as both sides showed plenty of energy straight out the traps, with the referee waving away a fourth minute Livi penalty claim after Stuart Findlay fouled Lewis Smith in the box.
Ten minutes saw Hearts go close, with Lawrence Shankland clipping a gorgeous reverse pass to send Claudio Braga scarpering into the box off the right, his shot dragging wide under pressure from Adam Montgomery.
After an even exchange in the opening quarter, Livingston claimed the lead after 25 minutes; Lewis Smith weaving through the Hearts line off the right and zipping the ball beyond Zander Clark at the near post.
The Lions almost added a quickfire second moments later as they began to shade possession; former Jambo Robbie Muirhead watching his header shoot just wide after an inviting cross into the box.
It was uninspiring fare after this, with chances few and far between at either goalmouth as both sides searched for a goal.
Five minutes to go and Livi went close to a second, Muirhead tip-toeing through the Hearts line before sliding in Tete Yengi - with Zander Clark palming his strike away from danger.
HT: Livingston 1-0 Heart of Midlothian
Change was required after the break, and McInnes turned to Greek winger Alexandros Kyziridis for inspiration as the Jambos chased an equaliser.
Kyzi's impact was immediate, registering a chance inside the first minute of the restart after clipping a strike towards goal, before setting up Hearts' equaliser after just anothr 60 seconds.
It was his dash to the byline that saw the ball whipped across goal for a waiting Claudio Braga - the Portuguese marksman planting an expert header across his man that sfaely nestled into the far corner.
Hearts were now on the front foot, and went close to a second after 56 minutes as Braga scarpered away down the right once more - his powerful strike only able to ripple the side netting.
There was a debut for club record signing Ageu from the bench, with the Brazillian midfielder trying his luck from distance after 76 minutes, with his powerful swipe well wide of Jerome Prior's goal.
Hearts had a huge chance to win it after 79 minutes as a ball forward was expertly brought down by Ageu and slid across to a waiting Braga, but he was only able to hit the post.
Deep into added time, Alexandros Kyziridis picked up the ball on the edge of the box and stroked a curling effort home to send the bumper away support into raptures.
Hearts return to action on the 13th September at Ibrox following the international break.
Livingston: Prior, Montgomery, McGowan, Pittman, Muirhead, Smith (Winter 73'), Bokila (Shinnie 58'), Finlayson, Sylla, Wilson, Yengi (McLennan 73')
Subs: Hamilton, Carey, McLennan, Winter, May, Shinnie, Kabongolo, Wanner, Lawal
Hearts: Clark, Kent, Halkett (Kyziridis 45'), Baningime (Kerjota 80'), Shankland, Braga (Kabangu 89'), Devlin, Spittal (Ageu 66'), Milne, Findlay, McEntee
Subs: McFarlane, Kingsley, Kabangu, Steinwender, Wilson, Magnusson, Kerjota, Ageu, Kyziridis
Hearts Debut: Ageu
