Joe Hart’s remarks as he announced his impending retirement from football at the end of this season started and ended on a common phrase: ‘heart and soul’. And if there is an apt description of what he put into his time at Celtic, that would be it.

Yes, there were bumps along the way. The football that Ange Postecoglou played pushed him out of his comfort zone, leading to some hairy moments with the ball at his feet, to say the least.

And just a few months ago, his suitability for the position of Celtic number one beyond this summer was being questioned after some dicey displays, not least his part in the 6-0 Champions League defeat to Atletico Madrid.

He himself has ended that debate by announcing that he will step away from professional football at the end of this season, ironically, just as he is enjoying arguably the best and most consistent run of form he has produced in a Celtic jersey.

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Celtic’s general performance level may have taken a nosedive since the end of the winter break, but Hart’s has taken the converse trajectory. He has come up with massive saves at Pittodrie, Easter Road, the SMiSA Stadium and at Celtic Park against Kilmarnock to ensure that this dip from the champions is not yet an insurmountable disaster.

There may have been a touch of recency bias then about the general regret expressed by Celtic supporters over the news when it broke, though it was probably more down to the fact that fans can spot a guy who is giving his all for their team a mile off.

And Hart, as well as proving he was still an accomplished goalkeeper at this level during his time in Glasgow, has certainly been that.

It was a marriage born of inconvenience for both parties, with Hart’s stock at an all-time low as he sat in Siberia at Tottenham Hotspur, and Celtic desperately searching for an answer between the sticks after the big-money flop of Vasilis Barkas.

But it was a happy union for the most part, and one that has provoked sorrow at its imminent termination.

“This is something I’ve thought about for a while,” Hart said.

“There is not right or wrong time, is there? The way this club works at the moment, there’s so much on it, there’s so much heart and soul poured into what we are doing as a football club.

“With the grand scheme of the club and the support base, and the conversations that go on around the goalkeeper position for next season, I just think it was really important, with the blessings of the club [to announce this now].

“I’ve had the conversations with the club, with Brendan (Rodgers) and Stevie Woods, and I felt it was important to get the message out.

“It takes one thing off the table that can be speculated over. I’m definitely not going to be there next season, I won’t be available to play football.

“I want to take that off the table and we can talk about why, and then push forward.”

While Hart will hope his announcement will allow him to focus on the here and now, for everyone else, it is only natural to look towards the summer and ponder how Celtic might fill the former England number one’s gloves.

A more pertinent question may be how they go about filling the leadership void, with Hart’s value to the club and manager Brendan Rodgers not solely confined to what he did in the 18-yard box.

Even when Hart’s form wobbled, he was a reliable and consistent presence within the dressing room, an example for teammates to follow and a blueprint for young players to adhere to if they wanted to wring the absolute maximum from themselves.

Whatever your views on his goalkeeping, his qualities as a human being are never questioned by those who know him. He fully bought into Celtic, understood the demands of the club, and that will no doubt colour his legacy with the supporters when he does eventually leave.

As too, may the next few months, of course, as he aims to go out on a high.

“I am aware time waits for no man – and I don’t want my body retiring me,” he said.

“That was one of the key factors, thinking I could really smash through the finishing line here.”

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If Celtic do go on and win the title, it may be viewed more as a team stumbling over the line by hook or by crook rather than smashing through it on current evidence, but one thing is for certain – Hart will be pouring both heart and soul into achieving that goal.

“To the people that know me – that really know me – they know that [checking out]’s not even a possibility.

“I was cautious of that, so I appreciate the open mindedness of the club and the fans when they see this and understand it.

“This is not someone who is checking out. This is someone who is just letting them know because they think it’s important.

“I can’t wait to have those conversations. I can’t wait to get into the ifs, buts and maybes, the whys and hows, the ups and downs and how I can pass on my experience for people to hopefully learn from or improve on, and maybe offer me some hindsight.

“The key message is those conversations are for after. This is the last time I’ll be talking about this.

“All I want to do is focus on the job in hand and representing this amazing club I play for and leaving my heart and soul out on the field.”