Ange Postecoglou can’t quite put his finger on what keeps his Celtic players coming back for more.

You’d think a season which has spanned 48 games across four competitions would require even a gentle cracking of the whip at some point, just to keep everyone on their toes. But the manager says he has not been forced to intervene on matters relating to motivation and application.

‘Relentless’ is the word Postecoglou uses, and just one domestic defeat all season suggests it is an appropriate one. He has been lauded for bringing a number of considerably talented footballers to Celtic over the past seasons, and clearly that judgement extends to assessing character as well as ability on the pitch.

These players will have their every sprint, tackle and shot recorded and analysed, their performances broken down in miniscule details. Those numbers will provide confirmation of the desire Postecoglou sees every day, but the ‘why’ is harder to pin down.

“I haven’t felt like I’ve needed to intervene to get them going or motivate them,” he said. “They are just really relentless in their approach.

“They have obviously been sort of motivated by something within this football club or something within their own group which makes them come in every day and disregard what has happened before and instead look at the next challenge and make sure they are ready for that.

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“It’s just my opinion but I think the standard they have set this year has been unbelievable. To be so consistent in their performance, scoring goals, has been incredible.”

 Presumably, though, that means there’s another side to Postecoglou these players haven’t had to reckon with yet?

“It has been said!” he smiled. “Sometimes a stern look is all it takes, mate. I learned that from my father.

“I haven’t had to. Not from that perspective. I want to make sure we are still evolving as a football team.

“I’ve got brilliant staff to help me and keep moulding this team. But in terms of attitude and character, the way they embrace new players into this football club is outstanding. They welcome them as if they are welcoming them into their home.

“It’s just incredible to see guys coming from all over the world and they feel like they are part of the family literally from the first day that they arrive. That is the environment and the culture they have created in there.”

It has been notable that a number of players signed by Postecoglou have bought wholesale into the history and tradition of the club itself, whether that be Kyogo Furuhashi’s rapport with supporters or Jota turning up at one of Glasgow’s most prominent Celtic pubs. The manager believes encouraging that level of buy-in has real value.

“I think it is important because you have a stronger understanding of what the most important people at the football club, the fans, are all about,” he said. “Part of that is the way we play, I think that is important. We are going to be a team that wants to excite our supporters and score goals. And you need to be a team that wins. That’s the standard that is set by all of the great teams at this football club.

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“You have to embrace that. You can’t reject that or try to change that. That’s what it is and you have to embrace it and use it to get the best out of yourselves.

“They are a really close group in the right way. It doesn’t mean they all hang out together because they are all at different stages of their lives, some are parents, some are single, some have different tastes and stuff.

“But that’s like any family, you want them to be themselves and to express themselves. But when it comes to the football club and to the way we want to behave and represent ourselves, they are all totally aligned.”

After clinching the title with victory over Hearts on Sunday, Celtic have four more league games to navigate before their season wraps up with the small matter of the Scottish Cup final. Postecoglou’s team can still set a new Premiership points total record of 107 if they are flawless across those final fixtures.

And, despite their status as heavy favourites to overcome Inverness Caledonian Thistle at Hampden on June 3, the manager says sustaining momentum is crucial ahead of a day where Celtic could complete an unprecedented eighth domestic treble.

“That’s what I’m talking about,” he said. “I don’t think that’s in my control: the players will do that themselves. I know they will come in this week and I know they are going to train like they have all year. We will tackle these four games the way we have tackled everything else.

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“We’ve got a cup final to prepare for and the best way to prepare for that is to be in really good rform. I'm sure they all want to play in the cup final and they are only going to play if they are in good form and taking their opportunities. We won’t change our approach.

“I think the last four or five weeks you can feel the lads have kind of tightened up in the way we are playing, knowing what’s at stake. We haven’t been as free-flowing as we were earlier in the year, which is understandable. And it’s felt like a long year because of the Champions League and the World Cup break. But I’m in no doubt that in the next training session they will be out there working as hard as they always have.

“We want to win, mate. I’m going to put teams out to win. That’s it. And the guys respect that, that’s what they want. They don’t want to be given anything they want to earn everything they get. If they play they will play because they have earned it. If I make decisions that go away from that there will be other guys asking questions as to why they’re not playing.”