John Souttar grabbed a stunning late winner to give Hearts a dream return to the top-flight.
The central defender had the freedom of Tynecastle to rise and meet Michael Smith's swirling free-kick just before the end of normal time to secure a fantastic victory for Robbie Neilson’s team.
But, if it was joy for the Jambos gaffer, it was a hammer blow to his counterpart Ange Postecoglou.
The Aussie looked to be on course for an opening night point when unlikely Celtic hero Anthony Ralston snared a superb second-half equaliser for his team to cancel out an early counter from Gary Mackay Steven.
Defeat was harsh on Celtic, but that mattered nothing to the hosts who celebrated a magnificent return to the top tier of the Scottish game.
It was a pulsating game which swung back and forth and victory was finally secured for Hearts by keeper Craig Gordon making two brilliant stops in injury time after Souttar’s big moment.
David Turnbull wasted a cracking chance when slicing wide and that would prove very costly to Celtic when Mackay Steven slotted a simple eighth-minute opener to signal Hearts’ return to the big time soon after they had unfurled the flag for last term’s Championship win.
Josh Ginnelly got the better of new Hoops signing Carl Starfelt and found Liam Boyce in the box.
The striker managed to keep the play alive and a sliding challenge from Nir Bitton nudged the ball across the six-yard box to give the Northern Irishman’s team-mate an easy tap-in.
Home wing-backs Smith and Alex Cochrane as well as visiting skipper Callum McGregor, Turnbull and Ismaila Soro all had more efforts before the break, but Neilson’s men led into the second period.
However, Postecoglou’s team hauled themselves back into the contest with a leveller eight minutes after the resumption.
Ralston took possession from Soro and worked a one-two with Odsonne Edouard before keeping his composure in the box to rifle a terrific finish beyond Gordon.
Both teams could have gone in front before Souttar’s winner. Scott Bain dived to save a header from sub Peter Haring and Gordon did the same at the other end to stop a Ryan Christie shot.
But Bain was left clawing thin air when the Hearts centre-back took advantage of slack marking to bullet home a header from Smith's wonderful delivery.
Tynecastle was rocking and Gordon sealed the deal with two special moments at the death. Firstly, the Hearts No.1 managed to divert a James Forrest shot over the bar and, from the resultant corner, he clawed away a header from Starfelt to ensure the stadium went wild at the end.
3 talking points
IN FOR A BENI
Hearts boss Neilson had no hesitation in thrusting his new capture into the line-up on the opening night and the 22-year-old was at the thick of the action. The former Everton man made tackles and covered ground and his use of the ball was intelligent. The midfielder made 12 appearances for the Toffees and will be a great acquisition if he keeps up the standards. This was a superb show.
Celtic’s new £4 million defender was handed a debut at the heart of the backline and it was an inauspicious opening when too easily beaten by Josh Ginnelly at the Mackay Steven goal. The Swede wasn’t convincing enough in a key situation deep in his own territory. Starfelt improved during the first-half and, barring one slip when he had to deck Boyce, the Scandinavian looked solid enough. However, although he almost levelled in stoppage time, his absence just a few seconds earlier along with the rest of the backline when Souttar notched was poor.
Celtic must still be rueing the day they allowed Gordon to walk out of the door to replace him with Vasilis Barkas. The Greek can’t even get in the team ahead of Bain and the veteran Hearts ace showed his top-level ability with two superb saves in injury time. No chance with Ralston’s goal, he proved himself still at the peak of his powers with the magnificent double save from Forrest and Starfelt in the frantic finale.