At a glance
Rampant Hearts powered eight ahead of Celtic at the top of the Scottish Premiership to bolster their early-season title credentials and deepen the struggles around the Celtic team.
A superb goal from Kyziridis and Lawrence Shankland's penalty gave the Hearts team a two-goal advantage that the reigning champions could not recover from.
Dane Murray - among three youth players in the Celtic XI - slashed into his own net in the early stages to put Hearts ahead at a bouncing Tynecastle, and it was the 22-year-old's foul that led to the penalty.
A stylish finish from McGregor of the season had swiftly equalized Hearts' opener, and the Swedish attacker almost put Rodgers' team in front, opting for finesse over power and allowing Alexander Schwolow to make a crucial stop.
But Derek McInnes' irrepressible Hearts seized control again to consign the visitors to successive league defeats for the initial occasion since 2023.
It also gives the Hearts a significant lead at the summit.
The last time they were this far ahead was in 2005-06 under their former manager, when they ultimately finished second - one of just four occasions that a team has failed to win the title having held such a lead in the last three decades.
The Hearts coach, whose Aberdeen side were runners-up to the champions on four occasions, has been working hard to downplay title talk, as Hearts seek their maiden league title since 1960.
The Celtic boss has experienced this previously at the club - both flawless and stuttering starts to a season. He's yet to finish second best.
But on the weekend's performance, this Hearts team showed they need to be taken seriously.
Hearts started with the confidence of a side unbeaten in the league this season - fans' favourite Kyziridis poked a cross in for the striker to fire off target.
Celtic didn't help themselves with some unusual sloppiness in possession and they buckled under their initial test.
Claudio Braga's header was touched on to a post by the Celtic keeper and Shankland's return ball was turned into the net by the hapless defender, in for the absent center-back.
The away side grew into the contest and started building moves. From a flowing attack, Sebastian Tounekti released the full-back to square for McGregor, who rolled in.
Apart from the Nygren chance, Celtic struggled to create much for lone frontman Jonny Kenny or his substitute Yamada amid the absence of stricken attackers their key strikers.
The home team rediscovered their energy and adaptability in creating chances in the opposition half. Kyziridis, a standout performer of the club's scouting network, struck low past Schmeichel from the just outside the area.
Immediately after, the defender fouled Braga in the right side of the box and Shankland scored. And it could've been an even more handsome win, 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 big-money recruit Engles.
The set-piece from Engles delivery was in sharp opposition to his midweek exploits in the Europa League win over their Austrian opponents and the Belgium international was then booked for a professional foul.
The Hearts manager: "The effort from the squad is evident, the togetherness. That's not sufficient on its own to win games consistently.
"What we have got, is good technical ability. You're seeing that from a lot of players who have been here previously. Recent additions are eager to show that.
"We've got a good thing going at the minute, but it's just one win. It's crucial for us to maintain this form. We've got much work ahead, plenty to improve. Following the initial fixtures is typically a benchmark of where you are."
The Celtic boss: "The second goal was disappointing from our perspective. We failed to push up when the play was recycled as a defensive unit so when they pass the ball, 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 still so early. It's just nine matches. Obviously, being eight points behind is not what we would want. The positive is there's so many games to play.
"We now have to focus on the here and now and look to achieve greater stability and more quality in our play."
The Glasgow club are returning to their stadium on midweek against promoted side Falkirk (19:45 GMT). At the identical hour in the Scottish Premiership, Hearts are at St Mirren.
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