Lena is a seasoned sports analyst with over a decade of experience in betting strategies and statistical modeling.
At a glance
Rampant Hearts powered eight ahead of Celtic at the summit of the Scottish top flight to strengthen their early championship claims and worsen the malaise around the Celtic team.
A superb goal from Kyziridis and a spot-kick from Shankland gave Derek McInnes' side a two-goal advantage that the title holders could not overcome.
Dane Murray - among three youth players in the Celtic XI - slashed into his own net in the early stages to put the home side ahead at a energetic Tynecastle, and it was the youngster's infringement that led to the spot-kick.
Callum McGregor's classy first goal of the season had swiftly equalized the first goal, and Benjamin Nygren almost put Celtic in front, opting for finesse over power and allowing the Hearts keeper to save from close range.
But Derek McInnes' irrepressible Hearts regained dominance to hand Celtic to back-to-back losses for the first time since 2023.
It also gives the Edinburgh side a significant lead at the top of the table.
The previous occasion they were this far ahead was in 2005-06 under George Burley, when they ended as runners-up - one of just four occasions that a team has failed to win the title having held such a lead in the past 27 years.
The Hearts coach, whose former team were runners-up to the champions on multiple times, has been working hard to downplay title talk, as the club seek their maiden league title since 1960.
Rodgers has seen it all before at Celtic - both perfect and shaky beginnings to a season. He's yet to finish second best.
But on the weekend's performance, this Hearts team showed they deserve serious consideration.
Hearts started with the self-assurance of a side undefeated in the league this season - the popular attacker delivered a ball for the striker to fire off target.
Celtic didn't aid their cause with some uncharacteristic carelessness in possession and they faltered under their initial test.
Claudio Braga's header was touched on to a post by the Celtic keeper and the follow-up from Shankland was turned into the net by the hapless defender, in for the injured Cameron Carter-Vickers.
The away side found their rhythm and started stringing passes together. From a flowing attack, the midfielder released the full-back to set up McGregor, who slotted home.
Apart from the opportunity for Nygren, Celtic found it hard to generate chances for striker Kenny or his replacement Shin Yamada amid the unavailability of injured forwards Kelechi Iheanacho and Daizen Maeda.
Hearts regained their intensity and adaptability in attacking from across the final third. The Greek forward, a standout performer of the club's scouting network, fired a low shot past Schmeichel from the just outside the area.
Almost straight away, the defender tripped the midfielder in the inside right channel and the penalty taker converted. And it could've been an more comprehensive victory, had substitute Ageu not been stopped by the shot-stopper.
The visitors' performance after the break was somewhat summed up in a couple of moments involving record signing Arne Engles.
The midfielder's wayward free-kick delivery was in stark contrast to his European display in the continental victory over their Austrian opponents and the Belgium international was then booked for a professional foul.
The Hearts manager: "You see how hard the players work, the togetherness. That's not sufficient on its own to win games week in, week out.
"What we have got, is skillful players. You're witnessing it from multiple individuals who have been here before. Recent additions are keen to demonstrate their quality.
"We're in a positive moment at the minute, but it's just one win. It's important for us to maintain this form. We've got much work ahead, loads to do. After the first two rounds is typically a benchmark of your standing."
Celtic manager Brendan Rodgers: "The second goal was disappointing from our perspective. We failed to push up when the play was recycled as a line so when they play it, they ought to be caught offside but weren't. We have got to do better with the shot.
"There's still so many points to play for. It's only the beginning. It's only nine games in. Obviously, being eight points behind is not what we would want. The comfort is there's so many games to play.
"We now have to focus on the present and look to find more consistency and more quality in our play."
The Glasgow club are back at home on midweek against promoted side Falkirk (19:45 GMT). At the same time in the Scottish Premiership, the Edinburgh outfit are at their opponents' ground.
Lena is a seasoned sports analyst with over a decade of experience in betting strategies and statistical modeling.