Well it has finally happened and boy, was it with a bang. After 69 games and just over 19 months of domestic domination, Celtic have lost a game.

Not quite a crisis just yet for Brendan Rodgers, but he will have learnt an awful lot from watching his side being battered at Tynecastle.

But here’s a thought. I think losing the unbeaten run will actually prove to be a blessing in disguise for all concerned at Celtic.

Read more: Celtic will now hit the reset button, says Brendan Rodgers

It has become like a millstone around the necks of the Celtic players. It has been more a case in recent months of not getting beaten, and, keeping the run going, than actually going out and winning.

They have lost that bit of freedom and swagger in their play, plus, it will be a wee bit of a reality check for some of the players who have lost form but been immune to criticism due to being an Invincible.

It’s not as if it hasn’t been coming either, as just a week before, they came within inches of losing it on the other side of Edinburgh.

In saying all that, they didn’t just lose it yesterday, they were absolutely blown away by a bold and brave Hearts side who went at Celtic right from the first whistle. On a tight and bumpy Tynecastle pitch, the Jam Tarts hustled and bullied Celtic into mistakes all over the pitch.

If you give good players time and space to play they will destroy you. Alternatively, if you get in players faces and don’t let them get their heads up, they can look decidedly average. That’s exactly what Hearts did, for 90-plus minutes. They had the courage to press high up the park as a team and squeezed the life out of Celtic.

Sure, you risk being opened up and exposed by doing this, but, football is about taking risks sometimes.

Read more: Celtic number comes up to end Invincible run as Hearts tally hits four​

Games against Celtic have become a bit of a freebie as no one expects them to lose. The challenge now is to get near that level every week. Huge credit must go to Craig Levein, a man who has taken loads of criticism by fans and pundits alike, but who is now slowly but surely turning Hearts back into a side that is difficult to play against and beat, especially at Tynecastle.

I know from personal experience, opposing Levein’s Hearts in the early 2000’s, that they could be a tough nut to crack. He knows what it takes to build successful teams and will be hoping to kick on and get up the table.

Not only has it been Craig’s organisation and tactics that have turned Hearts around, but so has his bravery, throwing in young guys like Harry Cochrane and Anthony McDonald, a move that has lifted the whole mood around Tynecastle.

It has proved to be a masterstroke. Fans love to see young kids coming through and will show them more patience than maybe some journeyman or foreign player. In Cochrane and McDonald, they have unearthed a couple of gems who deserve to be in the team regardless of age.

That performance also showed every other team in Scotland the way to get at Celtic. It’s not by sitting back and hoping Celtic have an off day, but by pressing them up the park and trying to expose Celtic’s big weakness, in central defence. And that was brutally exposed yesterday.

Read more: Celtic will now hit the reset button, says Brendan Rodgers

Looking at the level that Brendan Rodgers clearly wants to reach, both domestically and in Europe in the coming years, with this group of players, the performance of his two first-choice centre backs will have sent alarm bells ringing.

Celtic have already made moves to bring in the experienced Marvin Compper and for me, Rodgers needs to have a clear out in that area. I have never been impressed by Dedryk Boyata. I don’t think he is the answer at the back, defensively.

Jozo Simunovic has had injury problems and has at times looked pretty solid. However, he had a shocker yesterday against Hearts. Is he going to be a player you can trust in a European environment? I have my doubts.

Eric Sviatchenko meanwhile, now looks surplus and certain to leave the club. Now, if Celtic are serious about moving to that next level, they need to spend some serious money in this area of the team.

If they don’t, that soft centre will continue to be exposed against the best foreign opposition, and as we witnessed yesterday, domestically by any team focused on matching and beating them all over the pitch.